Some bits I'd like to share with the world

My quest to program a ATTiny85 with my Arduinon UNO using ISP

2011-11-28T02:48:00.001+02:00

While doing the Arduino advanced course at house4hack a while ago, the Ubuntu 11.10 (oneric) guys could not manage to program their ATTiny85 chips although the windows and Ubuntu 10.04 (Lucid) guys managed fine. Today I spent a lot of time trying to get it to work and FINALLY did. Below is the main errors I saw and how to fix it.

Error1:

Binary sketch size: 688 bytes (of a 8192 byte maximum)

avrdude: stk500_getparm(): (a) protocol error, expect=0x14, resp=0x14

avrdude: stk500_getparm(): (a) protocol error, expect=0x14, resp=0x01
avrdude: stk500_initialize(): (a) protocol error, expect=0x14, resp=0x10
avrdude: initialization failed, rc=-1
         Double check connections and try again, or use -F to override
         this check.

avrdude: stk500_disable(): unknown response=0x12

Solution1:
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1286589145

"I think I found one myself.
the problem is that the init request is sent 3 times but only one answer is expected, the following patch should fix":

bilibao@nbarizzi2:~/ELE/arduino-0022$ diff -u examples/ArduinoISP/ArduinoISP.pde /home/bilibao/sketchbook/fixed/fixed.pde
--- examples/ArduinoISP/ArduinoISP.pde  2010-12-24 23:12:25.000000000 +0100
+++ /home/bilibao/sketchbook/fixed/fixed.pde    2011-01-12 01:10:41.373212997 +0100
@@ -54,7 +54,7 @@
  pinMode(9, OUTPUT);
  pulse(9, 2);
}
-
+int initSent=0;
int error=0;
int pmode=0;
// address for reading and writing, set by 'U' command
@@ -399,7 +399,8 @@
  uint8_t ch = getch();
  switch (ch) {
  case '0': // signon
-    empty_reply();
+    if(! initSent) empty_reply();
+    initSent = 1;
    break;
  case '1':
    if (getch() == CRC_EOP) {

I applied the patch above manually and hurray I got a different error!

Error2:

Binary sketch size: 688 bytes (of a 8192 byte maximum)
avrdude: stk500_getsync(): not in sync: resp=0x15
avrdude: please define PAGEL and BS2 signals in the configuration file for part ATtiny85
avrdude: please define PAGEL and BS2 signals in the configuration file for part ATtiny85

avrdude: stk500_paged_write(): (a) protocol error, expect=0x14, resp=0x11
avrdude: stk500_cmd(): programmer is out of sync

Solution2:
Get the following version of the ArduinoISP and apply the patch from solution 1 again.
http://mega-isp.googlecode.com/files/ArduinoISP.04.zip
(found the solution here)

My tiny is now happily blinking away, at last.
I sommer reported this as a bug too, so it may stand a chance of getting fixed.

soldering 101 today

2011-11-26T12:34:00.000+02:00

We had a cool soldering course at house4hack today.

Even though I did some soldering before, I'm quite impressed by how much I improved today.(sorry for the fuzzy g1 photos)Before:

After:

ORA-00001: unique constraint violated

2011-11-16T18:36:00.000+02:00

(Pasted here for posterity so probably not an interesting read unless you actually have the same problem and found this while googling)One of my colleagues Leendert Visscher had this weird problem today with a Oracle+JPA+JBOSS getting a

java.sql.BatchUpdateException: ORA-00001: unique constraint violated

Even after making sure all the sequences were fine eg. like checking that quering a nexval and making sure it will not conflict with existing values, the error still persisted :(

The solution was to rebuild the index?!! FTW

We found it after getting the hint while googling a bit.

My kindle thoughts and experiences

2011-10-14T15:10:00.019+02:00

Lots of people at work asked me about this, so while I'm writing it down, I might as well blog it..

I bought a Kindle Keyboard, Wi-Fi, 6" E Ink Displayfor myself last year over Christmas - got it delivered for free to a contact in the US that came back to South Africa that time, saved +-R800.Last month I helped my grandma buy a Kindle DX, Free 3G, 3G Works Globally, Graphite, 9.7" Display with New E Ink Pearl Technology- ordered it on the Monday got it on the Thursday +-R400 delivery (double that with import duty:( ).

Here are some of my opinions about what to buy.

9"big DX vs 6"small

6" - nice and portable - fits in your cargo-pants-pocket/purse/small bag
9" - better for reading pdfs - the letters are quite small on the 6" but if you rotate it 90 degrees it is still readable
9" - double the price for 2.5 times the screen area (IIRC)
Because my grandma is a bit visually impaired (mainly got it to listen to audio books from audible.com) I made some adjustments to hopefully help her. We decided to get the bigger Kindle for her because it has ever so slightly bigger buttons, but they are better positioned and I could hack it a bit.

E-ink

I would not buy something that does not say e-ink i.e. black&white, no backlight, can read in the sun, looks exactly like paper and is an absolute joy to read.

Leather cover with built-in light

Its almost as expensive as the kindle itself.
Worth it in my opinion.
Uses the kindles own battery - never stuck with flat battery at the wrong time.
great for reading under the covers
With any cover you must be careful how you open it because if you open it on the wrong side you can crack your Kindle. I added some paper clamps and took off the levers for my grandma to avoid any nasty accidents (saw this tip on the interwebz):

Only buy from Amazon

Local importers pay the same price as you do and then add commission

Check the R/$ price before you buy

The 2 times I checked the Dx prices it varied from +-R3800 to R4200, just after I bought it the R/$ rocketed up another 40cent which whould have been another R400!

Buy international version if you are not in the US

When I bought mine, I had to go to the special international kindle page, maybe that changed..

3G or not?

3G version is 40% more expensive :(
Its handy to be able to buy books over 3G when away from any ADSL with wirless.
I think 3G coverage is done by MTN in RSA, so if you have bad 3G reception where you live then maybe it is not worth it..
I'm not that sorry that I didn't go for the 3G one, because I do most of my syncing and buying from home in any case.

FINALLY:

If you have not noticed it so far, I absolutely LOVE my kindle, I can almost not read anything else. Other cool features:

Has awesome text-to-speach for books bought from Amazon (DRM:( .awz) and free (.mobi) books
Can play audio books bought from audible.com, you can buy them directly from a wifi device but not from a 3G device!!?!
Can play mp3s for you in the background
Can play podcasts or mp3 audio books - just copy them into the audible folder on the device
Includes a free dictionary and you can look up any word while reading.
Make notes, bookmarks, underlinings (can even see commonly underlined stuff if you are too lazy to do it yourself:)
Calibre is the awesomest crossplatform e-book management tool ever! and works great with my Kindle.

I just could not sit it anymore

2011-09-21T00:36:00.006+02:00

Len Weincier opened my eyes to the possibility of a standing desk a couple of months ago and I've been pondering it ever since.
Recently I found myself in much pain when having to sit and work for extended periods of time (Since my baby son started sleeping in his own room about a month back I can't work in his room lying on my back any more).
It is so distracting that I'd rather stop working and go to bed.

Well tonight I could not sit it any more and I decided to try it out. I was thinking about all the things I'll need to move around if I want space in front of a wall in my study and how much work it will be, then it dawned on me I have everything I need to build a prototype and try it out.
My standing desk version 1.0 (to my wife's dismay I'm sure when she sees this in the morning):

Long-running preparations:

Learned to touch type (with the help of learning to type using the Colemak keyboard layout)
Got a proper usb keyboard to try this out.

Next steps:

I'm still googling to find out if its a good idea in the long term, but for now this seems much nicer.

Why and How I Switched to a Standing Desk (some more awesome prototypes :)
17 standing desks that will help you live longer (even a walking desk :) I may even try this treadputers some day since I have a manual treadmill standing around)
Are You Sitting Down? Why a Stand-Up Desk Might Save Your Life
Are Standing Desks Healthier Than Sitting?

Get some stickers to put on the index finger home keys. I saw Gary van der Merwe had them and I think it will help me a lot because this new keyboard has really tiny dots for feeling the where your index fingers should go.
See if I can come up with a better design with a higher spouse approval factor. It would be cool to have something that can easily convert between standing and sitting to avoid over-standing it.
Get a LCD screen so I don't have to balance my laptop so tenderly.
I can already see that my touchtyping skills will go to a next level with this because my hands are now under my laptop and thus it is much harder to steel a quick glimps (especially for seldomly used keys)

JPA not instantiating mapped collections.

2011-08-18T03:40:00.005+02:00

I struggled a while now to figure out why I am getting a NullPointerException
when trying to access a mapped collection:

@OneToMany(cascade = CascadeType.ALL, mappedBy = "cmTypedef")

private List cmParamdefs;

I instantiated a object, then em.merge() it but still I got a NPE.
I really thought that merge would populate all the fields.

Then I tried to make it Eager:

@OneToMany(cascade = CascadeType.ALL, mappedBy = "cmTypedef",

   fetch = FetchType.EAGER) 

private List cmParamdefs = new ArrayList();

Still no luck :(

So merge didn't do the trick, but trying everything I saw that if I do

em.flush();

em.refresh(ret);

after the merge, then like magic the collection is populated..

Finally I remember I had this issue before and the simple solution I have so far is
to manually instantiate the collection:

@OneToMany(cascade = CascadeType.ALL, mappedBy = "cmTypedef")

private List cmParamdefs = new ArrayList();

I'm not sure if this is the best practice, but it works and is simple..

I cancelled my uncapped ADSL account at Afrihost today (ADSL in South Africa)

2011-05-20T04:27:00.011+02:00

I'm being throttled so badly (down to +-7KBps on a 512kbps=80KBps line) that I had to turn on my prepaid account so I could view some web pages while downloading a couple of megs. I had to stop bittorrent too :( I only downloaded 40.9GB so far this month and I don't know why they need to throttle me after hours..

Some other user experiences:
http://handshake.co.za/2011/uncapped-adsl-in-south-africa/
http://www.carforums.co.za/viewtopic.php?f=5&t=36411&sid=4bfbaa0a65133fdee40f95c062a3208b
http://mygaming.co.za/forum/showthread.php/13410-Axxess-vs-Afrihost
http://mybroadband.co.za/vb/showthread.php/222441-Afrihost-Uncapped-Subscribers-Feedback/page82
http://mybroadband.co.za/vb/showthread.php/264071-Afrihost-uncapped-ADSL-account-move-why-it-was-done
http://www.bblounge.co.za/showthread.php?t=1563
http://forums.icreatehosting.co.za/viewtopic.php?f=13&t=63
http://mybroadband.co.za/vb/showthread.php/315785-so-far-Which-ISP-uncapped-is-the-best?p=5678667#post5678667

That settled it, now I just had to decide: mweb or openweb?
http://mybroadband.co.za/vb/showthread.php/316473-Mweb-or-Openweb
In the end I'm going for mweb because it is cheaper.

Compare prices:
http://pcbunny.co.za/adsl/uncapped-data-only/

I see mweb throttles bittorrent quite badly :(
http://outsourcehouse.co.za/afrihost-vs-gamco-vs-mweb-vs-openweb-uncapped-adsl-south-africa/

MWEB Uncapped ADSL claims questioned
http://mybroadband.co.za/news/adsl/20086-MWEB-Uncapped-ADSL-claims-questioned.html

I don't see much difference between the throttling of p2p stuff between mweb and afrihost:
http://wiki.vuze.com/mediawiki/index.php?title=Bad_ISPs#South_Africa

Bonus 1: You get 2 months free when signing up for 6 months at mweb:
http://www.mweb.co.za/productspricing/Get2MonthsFreeAdsl.aspx

Bonus 2: Telkom are upgrading their 512kbps lines to 1024kbps lines for free:
http://mybroadband.co.za/news/adsl/20112-Telkom-ADSL-speed-upgrades-begin.html
...mmmm maybe I should get the faster isp account too for an additional R70...
(will need to double check that my line is in deed 1024kbps...)

Bazaar on sourceforge.net

2011-05-09T03:17:00.003+02:00

(sorry if you get this twice, blogspot made it disappear..)

I've bean looking for a place to host a modular project which is being version controlled with Bazaar. I would have loved to use Launchpad, but I can't because of the following:

Launchpad only allows one level of branches (no hierarchy). My project is made up of a lot of sub-projects: I have a main branch which controls the sub-projects as bzr-externals.
Launchpad does not have a nice project wiki or any custom web content.

I saw that sourceforge.net now supports Bazaar, but I was a bit worried when I saw on their wiki that they only support Bazaar version 1.10 . It turns out that it is thankfully only an outdated doc:

[me@shell-21002 ~]$ bzr --version
Bazaar (bzr) 2.1.1
Python interpreter: /usr/bin/python 2.4.3
Python standard library: /usr/lib64/python2.4
Platform: Linux-2.6.18-...

(I don't seem to have rights to correct the wiki and I could not google the current version, so I'm documenting it here for you.)

I did test that I could upload nested branches. But unfortunately the code browsing tool on Sourceforge (loggerhead) does not display the nested branches :( Hopefully that is fixable..
Update: Alexandre Garnier kindly noted that there is a bug report for it.

Uncapped 512 kbps ADSL...so liberating

2011-04-28T16:45:00.000+02:00

Last week I decided I want faster internet so I upgraded my Telkom line to 512kbps (from 384kps) after a quick phone call and waiting a couple of days for the activation. In general my surfing experience didn't improve much but the odd download does come down much quicker, and concurrent downloads doesn't interfere that much with each other any more. I know people in other countries probably laugh at these oxwagon speeds in 2011, but c'mon this is Africa.

I finally took the plunge last night and went over to uncapped internet. Afrihost makes for a great impulse buy since they charge pro-rata for the first month and have instant activation for existing customers. I don't think I'll ever be able to go back. I'm already torrenting and and downloading big stuff like the latest ubuntu and XP service packs (for family m'kay you can't choose them..) that I usually would avoind or get through other means.

maven 3 - its time

2011-03-15T20:04:00.000+02:00

After getting some weird issues with my builds I tried out maven 3 again to see if it magically fixed things. It didn't fix that issue, but I'm quite impressed with maven 3 so far:

It can build subprojects in parallel which gives me quite a performance boost.
The other big thing for me is that "lots of bugs are fixed now", which is a bit hard to measure right away but will probably ensure a more enjoyable experience.

Richard Kolb asked for some benchmarks so here they are. It is probably a lot more beneficial for my 17 module project to build it in parallel.

It was done on my Intel i7 Q749 @ 1.73GHz with SSD
The second run of each hopefully avoids delays while "checking for updates"
Java version: 1.6.0_24
OS name: "linux" version: "2.6.35-27-generic" arch: "amd64" Family: "unix"
It includes a GWT widget compile
Ran mvn clean install in the maven reactor with 17 subprojects

== Apache Maven 2.2.1 (rdebian-4) ==
4 minutes 15 seconds
3 minutes 18 seconds
3 minutes 22 seconds

== Apache Maven 3.0.3 (r1075438; 2011-02-28 19:31:09+0200) (serial) ==
3:34.911s
3:14.637s

=== apache-maven-3.0.3/bin/mvn -T6 clean install (using 6 threads) ===
2:23.427s
2:23.224s

=== apache-maven-3.0.3/bin/mvn -T6 clean install (using 8 threads) ===
2:22.137s
2:19.600s

so I save about a minute (or 28%) when runing thing in parallel

I had to upgrade some maven plugins to allow things to be treadsafe with the help of this page:
https://cwiki.apache.org/MAVEN/parallel-builds-in-maven-3.html

Toshiba Qosmio X500-12V

2011-02-28T01:18:00.000+02:00

I got my new lappy a couple of months ago, so I better post already or hold my peace.
I'm quite impressed, although I haven't tried to get everything working yet still need to play with multitouch and the fingerprint reader . Suspend to disk didn't work and I haven't tried to suspend to ram yet, but it is booting so fast that I don't really need that.

I got a solid state and conventional harddrive, where the solid state disk performs about twice as good as the conventional one (was hoping for better, but it is ok).
SSD: 152.64 MB/sec
HDD: 89.22 MB/sec

* I Managed to migrate my previous installation (Ubuntu maverick) from my other laptop, moving around directories into special partitions (having most of the main os on the SSD but pointing /var/cache /var/log /var/tmp to the HDD)
* I had to fight a bit with grub and X to get it to work on the new hardware, but it was worth it in the end.
* I now get much better wireless reception:). (previously my connection died all the time:(
* The nvidia drivers works nicely which makes desktop effects work well - I can invert my desktop colours at last!
* Vista in a virtualbox works seamlessly for me now.
* bzr tests runs in 5 minutes now in stead of 18.
* gwt extensions compile in a minute now and does not lock up my laptop; previously it ran for over 5 minutes during which I could barely read e-mail because the system was so busy.
* Eclipse starts and stops a LOT quicker yay!
* Sound is really good (with the 3 watt harman/kardon 1by3's).
* Got the card reader working with some tweaking:
http://ubuntuforums.org/showthread.php?p=10302581

cleaning frequency of /tmp and /var/tmp

2010-12-11T13:17:00.000+02:00

/tmp normally gets cleared after every reboot on ubuntu which is a bit quick for me. For example I sometimes want to save a screenshot and maybe quickly edit it and e-mail it, but I don't want to loose it if my system reboots for whatever reason (including forgetting that I was busy with something).
It turns out that you can set how long to keep stuff in /tmp by setting TMPTIME in /etc/default/rcS to the number of days to keep stuff (I'm going for 7days now).
http://linuxers.org/article/differences-between-tmp-and-vartmp

Apparently you normally should put temp stuff you want to keep a bit longer in /var/tmp [1] but that does not seem to get cleared out regularly.
So I made a weekly cronjob to clean out stuff older than 60 days:/etc/cron.weekly/clean_var_tmp.sh

#!/bin/bash
days=60
tmpdir=/var/tmp/
find -P ${tmpdir} -type f -mtime +$days        -exec su amanica -c "notify-send 'weekly clean ${tmpdir}' 'rm {}'" \; -exec rm {} \;
find -P ${tmpdir} -type d -mtime +$days -empty -exec su amanica -c "notify-send 'weekly clean ${tmpdir}' 'rm {}'" \; -exec rm -r {} \;

http://ubuntu-virginia.ubuntuforums.org/showthread.php?t=1524077

[1] http://www.pathname.com/fhs/2.2/fhs-5.15.html

@Entity(name != table_name !!!

2010-10-27T01:27:00.000+02:00

Normally if you get "org.hibernate.hql.ast.QuerySyntaxException: is not mapped" then you used the table name in stead of the class name. In my case I'm ashamed to admit,

I though setting @Entity(name is setting the table name,

where in fact it is setting the JPQL alias!

I thought it was weird that you can set that and the @Table(name .

@Entity(name != table_name !!!
@Entity(name != table_name !!!
@Entity(name != table_name !!!
@Entity(name != table_name !!!
@Entity(name != table_name !!!

@Entity(name != table_name !!!

Thanks Matt Raible for showing me the light:

If you specify a name value for your @Entity annotation (for example
@Entity(name="person")), this will be the alias for HQL queries. If you
don't specify this value, the name will match the short name of your class (
Person). If you want to change the table name that's generated, use the
@Table
(http://java.sun.com/javaee/5/docs/api/javax/persistence/Table.html) annotation
with a "name" value.

http://www.mail-archive.com/users@appfuse.dev.java.net/msg18164.html

IncompatibleClassChangeError: Implementing class

2010-10-19T14:08:00.000+02:00

In my case this was caused by incompatible versions of hibernate in the classpath...

2010-10-19 12:40:32,271:ERROR   Problem encountered during View.servePage       - com.icesoft.faces.context.View
java.lang.IncompatibleClassChangeError: Implementing class
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClassCond(ClassLoader.java:632)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:616)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
        at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:983)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1501)
        at za.co.enerweb.nampower.report.hibernate.HibernateSessionFactory.(HibernateSessionFactory.java:60)

Overheating laptop

2010-10-13T17:16:00.000+02:00

A couple of weeks ago I could reliably get my laptop to overheat by just running the bazaar unit tests.

By googling I found that it could help to clean out the fan,
so I opened it a bit but gave up because I didn't have time to open it up completely.

Recently it got much worse, I could not even open eclipse without having a household fan directed at my laptop.

I decided today is the day. I had to remove about 30 screws and the processing unit heat sinks to get at them little radiators. They were a bit filthy of coarse, but its all cleaned now. I had to file off 1mm of a 3mm flat screwdriver bit so that I can unscrew about 11 2mm hexagonal screws.. . One screw got lost somewhere, I hope its not stuck somewhere where it can cause problems - that must be what doctors think if they are missing something after performing surgery.

It seems much better now, the fan doesn't even come on so often any more.

inconsistent datatypes with JPA.. eish

2010-10-12T13:26:00.000+02:00

I've been having some weird errors with JPA eg.
(pasted here so you can find it with google)

==
INFO - batching 1 statements: 1: insert into dds.DDS_EMAIL_STATUS (DOC_REGISTER_ID, EMAIL_ADDRESS_FROM,
EMAIL_ADDRESS_TO, LAST_UPDATE_TIME, MESSAGE_ID, SEND_DATETIME, STATUS_ID, SUBJECT, DDS_EMAIL_STATUS_ID)
values (1001, 'dds-test@example.com', 'test@example.com', to_date('10/12/2010 12:41:05', 'mm/dd/yyyy
hh24:mi:ss'), NULL, to_date('10/12/2010 12:41:05', 'mm/dd/yyyy hh24:mi:ss'), 0, 'testSend',
800)  {executed in 4 msec}
INFO - executeBatch()
ERROR - 2. PreparedStatement.executeBatch() batching 2 statements:
1:  insert into dds.DDS_EMAIL_STATUS_LOG (DATE_TIME, DDS_EMAIL_STATUS_ID, MESSAGE, DDS_EMAIL_STATUS_LOG_ID) values (to_date('10/12/2010 12:41:05', 'mm/dd/yyyy hh24:mi:ss'), '', 'html body:
html body', 750)
java.sql.BatchUpdateException: ORA-00932: inconsistent datatypes: expected NUMBER got BINARY
    at oracle.jdbc.driver.DatabaseError.throwBatchUpdateException(DatabaseError.java:343)
    at oracle.jdbc.driver.OraclePreparedStatement.executeBatch(OraclePreparedStatement.java:10720)
    at net.sf.log4jdbc.StatementSpy.executeBatch(StatementSpy.java:523)
    at org.apache.commons.dbcp.DelegatingStatement.executeBatch(DelegatingStatement.java:297)
    at org.apache.commons.dbcp.DelegatingStatement.executeBatch(DelegatingStatement.java:297)
    at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)
    at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:268)
    at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266)
    at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:167)
    at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
    at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
    at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027)
    at org.hibernate.ejb.AbstractEntityManagerImpl.flush(AbstractEntityManagerImpl.java:304)
    at org.apache.openejb.persistence.JtaEntityManager.flush(JtaEntityManager.java:130)
==
java.sql.SQLException: incompatible data types in combination in statement [alter table DDS_EMAIL_STATUS_LOG add constraint FKB7F2A8E6BAAD6FBB foreign key (DDS_EMAIL_STATUS_ID) references DDS_EMAIL_STATUS]
 at org.hsqldb.jdbc.Util.sqlException(Unknown Source)
 at org.hsqldb.jdbc.JDBCStatement.fetchResult(Unknown Source)
 at org.hsqldb.jdbc.JDBCStatement.executeUpdate(Unknown Source)
 at net.sf.log4jdbc.StatementSpy.executeUpdate(StatementSpy.java:694)
 at org.apache.commons.dbcp.DelegatingStatement.executeUpdate(DelegatingStatement.java:228)
 at org.apache.commons.dbcp.DelegatingStatement.executeUpdate(DelegatingStatement.java:228)
 at org.hibernate.tool.hbm2ddl.SchemaExport.execute(SchemaExport.java:383)
 at org.hibernate.tool.hbm2ddl.SchemaExport.create(SchemaExport.java:341)
 at org.hibernate.tool.hbm2ddl.SchemaExport.execute(SchemaExport.java:262)
 at org.hibernate.tool.hbm2ddl.SchemaExport.create(SchemaExport.java:211)
 at org.hibernate.impl.SessionFactoryImpl.(SessionFactoryImpl.java:343)
 at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1327)
 at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:867)
 at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:669)
...
Caused by: org.hsqldb.HsqlException: incompatible data types in combination
 at org.hsqldb.error.Error.error(Unknown Source)
 at org.hsqldb.error.Error.error(Unknown Source)
 at org.hsqldb.Table.checkColumnsMatch(Unknown Source)
 at org.hsqldb.TableWorks.checkCreateForeignKey(Unknown Source)
 at org.hsqldb.TableWorks.addForeignKey(Unknown Source)
 at org.hsqldb.ParserDDL.processAlterTableAddForeignKeyConstraint(Unknown Source)
 at org.hsqldb.ParserDDL.processAlterTable(Unknown Source)
 at org.hsqldb.ParserDDL.processAlter(Unknown Source)
 at org.hsqldb.StatementSchema.getResult(Unknown Source)
 at org.hsqldb.StatementSchema.execute(Unknown Source)
 at org.hsqldb.Session.executeCompiledStatement(Unknown Source)
 at org.hsqldb.Session.executeDirectStatement(Unknown Source)
 at org.hsqldb.Session.execute(Unknown Source)
==
javax.persistence.PersistenceException: org.hibernate.type.SerializationException: could not deserialize
    at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:614)
    at org.hibernate.ejb.AbstractEntityManagerImpl.remove(AbstractEntityManagerImpl.java:259)
    at org.apache.openejb.persistence.JtaEntityManager.remove(JtaEntityManager.java:107)
==
1:  update DDS_EMAIL_STATUS_LOG set DATE_TIME='10/12/2010 13:11:54.206', DDS_EMAIL_STATUS_ID='', MESSAGE='text body:
text body' where DDS_EMAIL_STATUS_LOG_ID=1 {FAILED after 0 msec}
java.sql.BatchUpdateException: data exception: string data, right truncation
 at org.hsqldb.jdbc.JDBCPreparedStatement.executeBatch(Unknown Source)
 at net.sf.log4jdbc.StatementSpy.executeBatch(StatementSpy.java:523)
 at org.apache.commons.dbcp.DelegatingStatement.executeBatch(DelegatingStatement.java:297)
 at org.apache.commons.dbcp.DelegatingStatement.executeBatch(DelegatingStatement.java:297)
 at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)
 at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:268)
 at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266)
 at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:168)
==

I tried different databases because it looked to me like the hsqldb is getting a bit confused with the column order. But in the end it turned out that I made a bit of a mistake:
I converted an embedded complex primary key to have a generated Id. In stead of annotating the referenced object with a @ManyToOne(optional = false)
it was still using @Column(name = "DDS_EMAIL_STATUS_ID"). After much debugging, googling and figuring out how to print the actual sql using http://code.google.com/p/log4jdbc-remix/ I figured out that I neglegted to change @Column to @ManyToOne.

Why is nothing ever easy ;-P

eclipse + tomcat + maven pain again

2010-10-02T23:36:00.000+02:00

Banging my head against the wall again today
because my app just does not want to start up :'(
Between eclipse, tomcat and maven my classpath was messed up, getting all sorts of exceptions like NoClassDefFoundError etc.

Finally I figured out again that for each project involved you have to check "Maven Dependencies"
in the "Order and Export" tab of the Java build path settings.
Then when you tell tomcat to include these projects,
it will actually include it and its dependencies.

I'm not sure how this got lost because my app used to work. Maybe when I imported the same project in
another workspace that got reset :(

cannot execute binary file

2010-09-07T23:58:00.000+02:00

I had this really weird issue on Ubuntu:
* An executable works fine on my laptop.
* Then I scp it to the server.
* On the server I get the following error messsage: "cannot execute binary file"
* So after some googling I found:

You are probably trying to run a 64-bit [executable] on a 32-bit Linux system...

http://www.kods.net/transferred-to-install-oracle-9i-in-linux-the-whole-document/

Go figure. I've been so spoiled with java and python, that I forget there are still things you need to compile for the platform you want to run it on...

Archiva gives the maven site plugin an invalid site_en.xml

2010-08-23T19:37:00.000+02:00

I got the following nasty error since friday:


$ mvn -U -e -X clean site
...
[DEBUG] Reading site descriptor from /home/amanica/.m2/repository/za/co/my_company/super-pom/1.0.3/super-pom-1.0.3-site_en.xml
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] SiteToolException: Error parsing site descriptor

Expected root element 'project' but found 'html' (position: START_TAG seen ... Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">\r\n<html>... @8:7)
[INFO] ------------------------------------------------------------------------
[DEBUG] Trace
org.apache.maven.lifecycle.LifecycleExecutionException: SiteToolException: Error parsing site descriptor
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:719)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalWithLifecycle(DefaultLifecycleExecutor.java:556)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:535)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
        at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
        at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
        at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
        at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
        at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
        at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
Caused by: org.apache.maven.plugin.MojoExecutionException: SiteToolException: Error parsing site descriptor
        at org.apache.maven.plugins.site.AbstractSiteRenderingMojo.createSiteRenderingContext(AbstractSiteRenderingMojo.java:232)
        at org.apache.maven.plugins.site.SiteMojo.renderLocale(SiteMojo.java:137)
        at org.apache.maven.plugins.site.SiteMojo.execute(SiteMojo.java:120)
        at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
        ... 17 more
Caused by: org.apache.maven.doxia.tools.SiteToolException: Error parsing site descriptor
        at org.apache.maven.doxia.tools.DefaultSiteTool.readDecorationModel(DefaultSiteTool.java:1298)
        at org.apache.maven.doxia.tools.DefaultSiteTool.getDecorationModel(DefaultSiteTool.java:1252)
        at org.apache.maven.doxia.tools.DefaultSiteTool.getDecorationModel(DefaultSiteTool.java:1260)
        at org.apache.maven.doxia.tools.DefaultSiteTool.getDecorationModel(DefaultSiteTool.java:511)
        at org.apache.maven.plugins.site.AbstractSiteRenderingMojo.createSiteRenderingContext(AbstractSiteRenderingMojo.java:225)
        ... 21 more
Caused by: org.codehaus.plexus.util.xml.pull.XmlPullParserException: Expected root element 'project' but found 'html' (position: START_TAG seen ... Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">\r\n<html>... @8:7)
        at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.parseDecorationModel(DecorationXpp3Reader.java:619)
        at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.read(DecorationXpp3Reader.java:1387)
        at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.read(DecorationXpp3Reader.java:1401)
        at org.apache.maven.doxia.tools.DefaultSiteTool.readDecorationModel(DefaultSiteTool.java:1294)

It turns out that maven looks for a site_en.xml for my parent project on archiva and archiva seems to generate a return file which is actually an error message.
The maven site plugin then tries to parse it and fails horribly :(
I worked around this by just adding the following content to src/site/site_en.xml in my parent project and everything was well!


<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/DECORATION/1.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/DECORATION/1.0.0 http://maven.apache.org/xsd/decoration-1.0.0.xsd">
  <body>
  </body>
</project>

I got really frustrated by this cryptic error message. I wanted to bash my head against the table and throw my laptop against the wall. Instead I cried out to God and not long after that I figured it out. Some would say thats just coincidence, I say: "Thank God", "Praise God" and "Why didn't I ask You sooner?".

Chromium happy again

2010-08-20T14:39:00.000+02:00

After getting the message below on each chromium start for months, I finally googled it:


Your profile could not be opened correctly.
Some features may be unavailable.  
Please check that the profile exists and you have permission to read and write its contents.

The solution for me was simple:

rm ~/.config/chromium/Default/History

I can't believe I suffered so long with a broken awesomebar which never found new history :(
Previously I assumed its something broken in chromium that would get fixed by a newer Ubuntu packages. The fix never came so I'm really happy that I finally found the solution today:
see Ariel's solution.

Apache url filtering corrupts compressed output.

2010-06-28T16:52:00.000+02:00

While trying to set up Hudson behind apache again, I kept on getting garbage out.
After some googling I realized Hudson compress its output, therefore you can not use the normal proxy-html filter to modify urls coming from hudson:

SetOutputFilter proxy-html

Instead you can use the following:

SetOutputFilter INFLATE;proxy-html;DEFLATE
ProxyHTMLURLMap http://your_server:8080/hudson /hudson

http://wiki.uniformserver.com/index.php/Reverse_Proxy_Server_2:_mod_proxy_html_2
But since hudson seems to be well behaved it even better to just not use SetOutputFilter and ProxyHTMLURLMap.

http://wiki.hudson-ci.org/display/HUDSON/Running+Hudson+behind+Apache

Internet Explorer 7 with Wine

2010-06-24T10:35:00.000+02:00

After searching a lot and trying some recipes, the following worked beautifully for me to install Internet Explorer 7 on ubuntu 10.04 (lucid)
http://rkpisanu.altervista.org/doku.php?
id=wineie7eng#internet_explorer_7_with_wine
(I changed the last step to get it to work for me, because its installed in your home dir, not in your current dir)

Download dependencies:
sudo apt-get install wine cabextract

Download and run IE4WINE:
Warning: All wine program running must be closed before install and run IE4WINE
wget http://rkpisanu.altervista.org/download/ie4wine
chmod +x ./ie4wine
./ie4wine

Finally:
type ~/wineie7 (Stable Version )
type ~/wineie7https (Unstable Version with https support)

Archiva On GlassFish with Derby

2010-06-24T01:30:00.000+02:00

I added the following to the archiva wiki, but keeping a copy here for reference and backup.
https://cwiki.apache.org/confluence/display/ARCHIVA/Archiva+On+GlassFish+with+Derby
(based on https://cwiki.apache.org/confluence/display/ARCHIVA/Archiva+on+GlassFish+with+mySQL)

Glassfish web configuration

Deploy the war file on your Glassfish server from the admin page (http://localhost:4848).
Or copy the the war file into your <GLASSFISH_FOLDER>/domains/domain1/autodeploy/archiva.war
Glassfish file configuration
Edit the file <GLASSFISH_FOLDER>/domains/domain1/config/domain.xml to add the following tags:

Go to Ressources -> JavaMail Sessions and create a new ressource with jndi-name='mail/Session', otherwise you will get "Error creating bean with name 'mailSession'" on startup. Or add it to the config file:


...
<resources>
    <mail-resource from="me@email.example.com" host="email.example.com" jndi-name="mail/Session" object-type="user"
        store-protocol="imap" store-protocol-class="com.sun.mail.imap.IMAPStore" 
        transport-protocol="smtp" transport-protocol-class="com.sun.mail.smtp.SMTPTransport" 
        user="me"/>
...

Set appserver.base and appserver.home properties

Ensure that the property appserver.base is set. Archiva uses this to locate log files.


...
<java-config ...
    <jvm-options>-Dappserver.base=${com.sun.aas.installRoot}/domains/domain1
    <jvm-options>-Dappserver.home=${com.sun.aas.installRoot}/domains/domain1
...

JDBC resources


...
</applications>
<resources>
    <jdbc-resource pool-name="archivaUsersPool" jndi-name="jdbc/users" />
    <jdbc-resource pool-name="archivaPool" jndi-name="jdbc/archiva" />
..

Connection pool


    <jdbc-connection-pool datasource-classname="org.apache.derby.jdbc.EmbeddedXADataSource" res-type="javax.sql.XADataSource" name="archivaUsersPool">
      <property name="databaseName" value="/archiva/data/databases/users" />
      <property name="connectionAttributes" value=";create=true" />
    </jdbc-connection-pool>
    <jdbc-connection-pool datasource-classname="org.apache.derby.jdbc.EmbeddedXADataSource" res-type="javax.sql.XADataSource" name="archivaPool">
      <property name="databaseName" value="/archiva/data/databases/arvhiva" />
      <property name="connectionAttributes" value=";create=true" />
    </jdbc-connection-pool>

Resources ref


<servers>
<server config-ref="server-config" name="server">
...
<resource-ref enabled="true" ref="jdbc/users"/>
<resource-ref enabled="true" ref="jdbc/archiva"/>
...

Now restart you Glassfish server, and open the archiva location. The last thing you have to do is create the admin user.

dns cache

2010-04-15T11:17:00.000+02:00

I installed dnsmasq a long time ago, but it turns out I never told my dhcp to use it.
All done now thanks to the following post:
http://www.ubuntugeek.com/local-dns-cache-for-faster-browsing-on-ubuntu-machine.html

My steps (for in case I need to do it again :) :
sudo apt-get install dnsmasq

Now edit /etc/dhcp3/dhclient.conf
and uncomment the following line:

prepend domain-name-servers 127.0.0.1;

I didn't have a /etc/dnsmasq.conf , and it does not seem to be needed because my dns caching works fine now without it; I assume its got good defaults.

To test it quickly add nameserver 127.0.0.1 to the top of /etc/resolv.conf
(it normally gets overwritten by the network manager)

dig yahoo.com

You will see something like

;; Query time: 38 msec

there.
Now do it again, and you should see something like:

;; Query time: 2 msec

sweet!

Vaadin addons and maven and eclipse.

2010-04-07T17:27:00.000+02:00

Afters struggling for almost 3 days, I finally got some vaadin add-ons working for me.
No matter what I did, I could not get maven to compile the custom widget sets :'-(

Wanting to do it with maven I started off with the instructions at http://dev.vaadin.com/wiki/Articles/MavenIntegration.

I got error messages like:

Failed to load the widgetset: 
/my-project/VAADIN/widgetsets/my.company.my.project.widgetset.My_ProjectWidgetset/
my.company.my.project.widgetset.My_ProjectWidgetset.nocache.js?1270654337749

Building it with the eclipse plugin said:

Compiling widgetset my.company.my.project.widgetset.My_ProjectWidgetset
Updating GWT module description file...
07 Apr 2010 5:46:09 PM com.vaadin.terminal.gwt.widgetsetutils.ClassPathExplorer getAvailableWidgetSets
INFO: Widgetsets found from classpath:
 com.vaadin.terminal.gwt.DefaultWidgetSet in jar:file:/stf/opt/maven/repository/com/vaadin/vaadin/6.2.6/vaadin-6.2.6.jar!/
 my.company.my.project.widgetset.My_ProjectWidgetset in file:/stf/prj/My_Project/src/main/resources

Done.
Starting GWT compiler
Widgetset compilation completed

But when running the webapp, I got:

Widgetset does not contain implementation for org.vaadin.browsercookies.BrowserCookies. Check its @ClientWidget mapping, widgetsets GWT module descrioption file and re-compile your widgetset. Unrendered UIDL:
 
org.vaadin.browsercookies.BrowserCookies(NO CLIENT IMPLEMENTATION FOUND) id=PID7
 
variables
Widgetset does not contain implementation for com.github.wolfie.meteorcursor.MeteorCursor. Check its @ClientWidget mapping, widgetsets GWT module descrioption file and re-compile your widgetset. Unrendered UIDL:
 
com.github.wolfie.meteorcursor.MeteorCursor(NO CLIENT IMPLEMENTATION FOUND) id=PID8 gr=75 th=10 pl=1000 di=2 im=theme://images/logo.png fr=0 disabled=false

I thought that it was building, since the addons that I wanted to use got detected.
Little did I know that it was not actually building!
Building with maven said:

[INFO] Updating widgetset my.company.my.project.widgetset.My_ProjectWidgetset
[INFO] establishing classpath list (scope = compile)
[ERROR] 07 Apr 2010 5:38:31 PM com.vaadin.terminal.gwt.widgetsetutils.ClassPathExplorer getAvailableWidgetSets
[ERROR] INFO: Widgetsets found from classpath:
[ERROR]  com.github.wolfie.meteorcursor.MeteorcursorWidgetset in jar:file:/stf/opt/maven/repository/com/github/wolfie/meteorcursor/1.0.0/meteorcursor-1.0.0.jar!/
[ERROR]  org.vaadin.browsercookies.widgetset.BrowserCookiesApplicationWidgetset in jar:file:/stf/opt/maven/repository/com/vaadin/sami/browsercookies/1.0.2/browsercookies-1.0.2.jar!/
[ERROR]  com.vaadin.terminal.gwt.DefaultWidgetSet in jar:file:/stf/opt/maven/repository/com/vaadin/vaadin/6.2.6/vaadin-6.2.6.jar!/
[ERROR]  my.company.my.project.widgetset.My_ProjectWidgetset in file:/stf/prj/My_Project/src/main/resources
[ERROR]

The reason it was not building was because I was trying to use the stable version of the gwt-maven-plugin: 1.2
After reading this forum post again, I tried 1.3-SNAPSHOT of this plugin; and all my troubles went away.

So now I build it with maven, and it should give output like this:

[INFO] [gwt:compile {execution: default}]                                                                                                                    
[INFO] using GWT jars from project dependencies : 1.7.1                                                                                                      
[INFO] auto discovered modules [za.co.enerweb.ebr.gui.vaadin.widgetset.Ebr_vaadin_webWidgetset]                                                              
[INFO] establishing classpath list (scope = compile)                                                                                                         
[INFO] establishing classpath list (scope = compile)                                                                                                         
[INFO] establishing classpath list (scope = compile)                                                                                                         
[INFO] establishing classpath list (scope = compile)                                                                                                         
[INFO] establishing classpath list (scope = compile)                                                                                                         
[INFO] establishing classpath list (scope = compile)                                                                                                         
[INFO] Compiling module my.company.my.project.widgetset.My_ProjectWidgetset                                                                       
[INFO]    Scanning for additional dependencies: jar:file:/stf/opt/maven/repository/com/vaadin/vaadin/6.2.6/vaadin-6.2.6.jar!/com/vaadin/terminal/gwt/client/DefaultWidgetSet.java                                                                                                                                           
[INFO]       Computing all possible rebind results for 'com.vaadin.terminal.gwt.client.WidgetMap'                                                             
[INFO]          Rebinding com.vaadin.terminal.gwt.client.WidgetMap                                                                                            
[INFO]             Invoking                                                 
[INFO]                Detecting Vaadin components in classpath to generate WidgetMapImpl.java ...                                                             
[INFO]                Widget set will contain implementations for following components:                                                                       
[INFO]                  com.github.wolfie.meteorcursor.MeteorCursor                                                                                           
[INFO]                  com.vaadin.ui.AbsoluteLayout                                                                                                          
[INFO]                  com.vaadin.ui.Accordion                                                                                                               
[INFO]                  com.vaadin.ui.Button                                                                                                                  
[INFO]                  com.vaadin.ui.CheckBox                                                                                                                
[INFO]                  com.vaadin.ui.ComboBox                                                                                                                
[INFO]                  com.vaadin.ui.CssLayout                                                                                                               
[INFO]                  com.vaadin.ui.CustomComponent                                                                                                         
[INFO]                  com.vaadin.ui.CustomLayout                                                                                                            
[INFO]                  com.vaadin.ui.DateField                                                                                                               
[INFO]                  com.vaadin.ui.Embedded                                                                                                                
[INFO]                  com.vaadin.ui.Form                                                                                                                    
[INFO]                  com.vaadin.ui.FormLayout                                                                                                              
[INFO]                  com.vaadin.ui.GridLayout                                                                                                              
[INFO]                  com.vaadin.ui.HorizontalLayout                                                                                                        
[INFO]                  com.vaadin.ui.Label                                                                                                                   
[INFO]                  com.vaadin.ui.Link                                                                                                                    
[INFO]                  com.vaadin.ui.ListSelect                                                                                                              
[INFO]                  com.vaadin.ui.MenuBar                                                                                                                 
[INFO]                  com.vaadin.ui.NativeButton                                                                                                            
[INFO]                  com.vaadin.ui.NativeSelect                                                                                                            
[INFO]                  com.vaadin.ui.OptionGroup                                                                                                             
[INFO]                  com.vaadin.ui.OrderedLayout                                                                                                           
[INFO]                  com.vaadin.ui.Panel                                                                                                                   
[INFO]                  com.vaadin.ui.PopupView                                                                                                               
[INFO]                  com.vaadin.ui.ProgressIndicator                                                                                                       
[INFO]                  com.vaadin.ui.RichTextArea                                                                                                            
[INFO]                  com.vaadin.ui.Select                                                                                                                  
[INFO]                  com.vaadin.ui.Slider                                                                                                                  
[INFO]                  com.vaadin.ui.SplitPanel                                                                                                              
[INFO]                  com.vaadin.ui.TabSheet                                                                                                                
[INFO]                  com.vaadin.ui.Table                                                                                                                   
[INFO]                  com.vaadin.ui.TextField                                                                                                               
[INFO]                  com.vaadin.ui.Tree                                                                                                                    
[INFO]                  com.vaadin.ui.TwinColSelect                                                                                                           
[INFO]                  com.vaadin.ui.Upload                                                                                                                  
[INFO]                  com.vaadin.ui.UriFragmentUtility                                                                                                      
[INFO]                  com.vaadin.ui.VerticalLayout                                                                                                          
[INFO]                  com.vaadin.ui.Window                                                                                                                  
[INFO]                  org.vaadin.browsercookies.BrowserCookies                                                                                              
[INFO]                Done. (2seconds)                                                                                                                        
[INFO]    Compiling 1 permutations                                                                                                                            
[INFO]       Permutation compile succeeded                                                                                                                    
[INFO]    Linking into /stf/prj/My_Project/src/main/webapp/VAADIN/widgetsets                                                                          
[INFO]       Link succeeded                                                                                                                                   
[INFO]    Compilation succeeded -- 40.785s

To be able to serve my webapp using tomcat launched from eclipse I need to compile the GWT stuff into src/main/webapp . So unlike the instructions I mention at the top of this post, some key parts of my pom is as follows:

  <properties>
    <vaadin-widgets-dir>src/main/webapp/VAADIN/widgetsets</vaadin-widgets-dir>
  </properties>
  <build>
    <plugins>
      <!-- Compiles your custom GWT components with the GWT compiler -->
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>gwt-maven-plugin</artifactId>
        <version>1.3-SNAPSHOT</version>
        <executions>
          <execution>
            <configuration>
              <webappDirectory>${vaadin-widgets-dir}</webappDirectory>
              <extraJvmArgs> -Dgwt.style=PRETTY -Xmx512M -Xss1024k</extraJvmArgs>
            </configuration>
            <goals>
              <goal>resources</goal>
              <goal>compile</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
      <!-- Updates Vaadin 6.2 widgetset definitions based on project dependencies -->
      <plugin>
        <groupId>com.vaadin</groupId>
        <artifactId>vaadin-maven-plugin</artifactId>
        <version>1.0.0</version>
        <executions>
          <execution>
            <goals>
              <goal>update-widgetset</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <artifactId>maven-clean-plugin</artifactId>
        <configuration>
          <filesets>
            <fileset>
              <!-- also delete the generated vaadin web content -->
              <directory>${vaadin-widgets-dir}</directory>
            </fileset>
          </filesets>
        </configuration>
      </plugin>
    </plugins>
  </build>

vaadin 6.3 ant build target

2010-03-04T10:42:00.000+02:00

The vaadin source web page still has out-dated build instructions.
I tried:

vaadin/6.3/build>$ ant package-linux                                                                                                         
Buildfile: build.xml                                                                                                        

BUILD FAILED
Target "package-linux" does not exist in the project "Vaadin". 

Total time: 0 seconds

Looking at the following I realised that things have changed a bit:

$ ant -p
Buildfile: build.xml

Main targets:

 build              Build package required files, without packing them.
 compile-widgetset  Compiles the widgetset given as the first parameter
 package-all        Build public packages.                             
 package-jar        Create vaadin-x.y.z.jar file.                      
 package-jar-quick  Create vaadin-x.y.z.jar file quick.                
 test-build         used for testing build.xml                         
 test-package       used for testing build.xml                         
Default target: package-all

So I tried the following starting building like crazy:

$ ant package-all                                                      
Buildfile: build.xml
...

But it got stuck on:


manual-checkout:
     [echo] Checking out manual from repository http://dev.vaadin.com/svn/doc/trunk
    [mkdir] Created dir: /stf/prj/fs/vaadin/6.3/build/checkout

Finally I did:

$ ant package-jar

and the jar finally got built!


BUILD SUCCESSFUL
Total time: 10 minutes 49 seconds

Will try out package-jar-quick next...

This made me shout out complaints about ant (ask my co-workers) and fall in love with maven all over again.

How to make Archiva less paranoid about passwords

2010-03-02T18:53:00.000+02:00

After just 3 login attempts a user's account is locked by Archiva, which is quite bad if a whole team and continuous integration servers uses the same account.

I think you should just add an exponentially growing timeout to when the user can log in (maybe per source ip) or at least make it configurable from the frontend. But anyways, for our internal/firewalled archiva this sort of thing is a bit of over kill.

I finally found out how to convince it to be more lenient.
Just add the following content:

security.policy.password.expiration.days=999999
security.policy.password.expiration.enabled=false
security.policy.allowed.login.attempt=300
security.policy.password.previous.count=1
security.policy.password.rule.reuse.enabled=false

to the equivalent file to your system:

glassfish_2.1/domains/archiva/lib/classes/org/apache/maven/archiva/security.properties

http://osdir.com/ml/users-archiva-apache/2009-02/msg00031.html

Why can't icefaces give proper error messages? II

2009-12-23T14:13:00.000+02:00

After days of searching and experimentation it seems that its not possible to dynamically import
a .jspx file into another (one which is loaded from a jar, and the src location is supplied by the backing bean).

I'm trying to embed iframes now, but as soon as the iframes render, icefaces freezes up and does not send any events again. The only clue was this javascript error:

Error: no element found
Source File: http://localhost:17080/EbrWeb/block/receive-updated-views
Line: 1

After searching and a hunch that concurrently loading jspx pages breaks icefaces, I looked at the portlet sample
(ICEfaces-1.8.2-src/icefaces/samples/portlet/location/web/WEB-INF/web.xml).

I found that if I include the following in my web.xml, it works! Hurray!

<context-param>
  <param-name>com.icesoft.faces.concurrentDOMViews</param-name>
  <param-value>true</param-value>
</context-param>

This makes sense because I want to load several iceface pages in iframes in my main page.

Why can't icefaces give proper error messages?

2009-12-10T23:38:00.000+02:00

SEVERE: StandardWrapperValve[Persistent Faces Servlet]: PWC1406: Servlet.service() for servlet Persistent Faces Servlet threw exception
java.lang.Exception: javax.faces.FacesException: Problem in renderResponse: null

was trying to tell me:

<ice:tree> needed to be encapsulated inside an <ice:form>.

http://seamframework.org/Community/ProblemWithIceTree#comment101040

A+

2009-12-01T21:24:00.000+02:00

"a plus", short for "a plus tard" (French, pronounced ah-plu-tar), that is "see you later".
Used to end an informal email, or a chat. Equivalent to "C U"
http://www.urbandictionary.com/zazzle.products.php?defid=1461004

You can listen to the pronunciation here: http://www.forvo.com/word/a_plus_tard/

pycurl does not like bad certificates

2009-11-30T23:27:00.000+02:00

I keep on hitting this once in a blue moon (maybe after dist-upgrading), pushing to a smart server over https I get the following:

bzr: ERROR: Connection error: curl connection error (server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none)        
on https://mycompany/bzr/aprojectrepo/mybranch/.bzr/smart

And every time it takes me some time to figure out how to fix it, so I'm noting it here for future reference:
* remove python-pycurl
* or use "http+urllib://"

https://bugs.launchpad.net/bzr/+bug/365874

I suppose I should help fix this, but I don't see myself getting round to that any time soon.

happy karmic day

2009-11-24T20:42:00.001+02:00

My upgrade from jaunty to karmic was not quite rosy.
My man two problems were that my sound and touchpad stopped working.
Thankfully its all sorted out now (I hope).

My touchpad wasn't working because of using the wrong kernel - after upgrading to karmic, it didn't boot using the karmic kernel by default, I had to use grub editor to change that.
But then I could not boot. I had to go fix up my grub menu:
sudo vim /boot/grub/menu.lst
I had


title Ubuntu 9.10, kernel 2.6.31-14-generic (recovery mode)
root

in stead of


title Ubuntu 9.10, kernel 2.6.31-14-generic (recovery mode)
root (hd0,0)

(it was complaining that it could not find a kernel image at the specified location or something)

the sound was also related to using the wrong kernel, but also due to some pulsaudio issues see HOWTO: PulseAudio Fixes & System-Wide Equalizer Support - Ubuntu Forums

[update]
mmm... the first kernel update broke it again :(
I finally heeded Robert's advice to do:

sudo update-grub

https://bugs.launchpad.net/ubuntu/+source/grub/+bug/470265
My menu.lst looks fine now, but still need to reboot and test it.

Kalternatives

2009-11-21T15:48:00.000+02:00

I found this cool package today:

sudo apt-get install kalternatives

From the package info:


Kalternatives offers a GUI to configure the alternative systems (a
system that allows you to select one alternative file for many in the
filesystem).
Kalternatives is available as KDE configuration module, integrated by default
into KDE's System Settings.

This is an advanced GUI of the update-alternatives program shipped with dpkg.

Some of the options I wanted to customise:


desktop-splash
usplash-artwork (usplash-theme)
x-terminal-emulator
x-window-manager
x-www-browser

Project Lombok: Put an End to Java Verbosity

2009-10-31T01:14:00.000+02:00

If you're interested in java programming involving lots of beans, this is a crazy cool tool.

Its a combination of a compile-time and a development-time code generator, which has made Java POJO verbosity history.
It uses annotation magic to implement all the repetitive boring bean methods (getters, setters, equals, hashCode, toString)
without them actually cluttering your classes. Thats right it generates invisible code!

Now you have to watch the video at:
http://projectlombok.org/

You can reed this introductory article:
http://www.devx.com/Java/Article/42946/1954

See some other cool examples to look at:
http://projectlombok.org/features/Data.html
http://projectlombok.org/features/Cleanup.html (I was trying to implement this one just a couple of weeks ago)
http://projectlombok.org/features/EqualsAndHashCode.html

I came across lombok while trying to figure out if I can get eclipse to also generate the .equals and .hashCode methods
on new JPA entities like netbeans does. turns out it I don't really need that any more.

Saving a list of your Ubuntu packages and installing them again somewhere else

2009-10-17T16:30:00.000+02:00

When you have to leave your old installation behind and have to move to a new installation of Ubuntu. You can install all the packages you used to have in 3 easy steps. Then you just need to copy over your home folder and voi-la your new installation is almost exactly like you used to have. On other operating systems this takes a week or so, and you keep on discovering things you forgot.

So for the packages you do on your old install:

dpkg --get-selections > installed-software

copy the installed-software file over to your new install and:

dpkg --set-selections < installed-software 
dselect

Like magic. And if you have a local apt-cacher-ng, you don't even need to download everything again. Alternatively you can copy over your /var/cache/apt/archives/ before doing the second part. http://www.arsgeek.com/2006/09/19/ubuntu-tricks-how-to-generate-a-list-of-installed-packages-and-use-it-to-reinstall-packages/ http://ubuntu-sos.blogspot.com/2008/06/how-to-create-and-restore-list-of-all.html

(Ice)faces hates me and Richard

2009-10-13T02:51:00.000+02:00

After Richard Kolb and I have struggled with this for days, I finally cracked it.

We defined some dropdowns, and radio buttons in icefaces eg:

<ice:selectOneRadio id="reportColumnIndexRadio"
    value="#{scratchPad.reportColumnIndex}"
     partialSubmit="true"
     layout="pageDirection">
    <f:selectItems
        value="#{scratchPad.reportColumnIndexSelectItemList}" />
</ice:selectOneRadio>

<ice:selectOneMenu id="reportColumnIndex"
    value="#{scratchPad.reportColumnIndex}"
    partialSubmit="true">
    <f:selectItems
        value="#{scratchPad.reportColumnIndexSelectItemList}" />
</ice:selectOneMenu>

but when a new item was selected nothing happened, we just got this VERY cryptic log entry e.g:

sourceId=reportEditorForm:j_id14[severity=(ERROR 2), 
summary=(reportEditorForm:j_id14: 
An error occurred when processing your submitted information. ),
detail=(reportEditorForm:j_id14:
An error occurred when processing your submitted information. )]

After hours of (debugging, guessing, googling, repeat) loops,
I finally found this link which explains it a number of times:
http://www.icefaces.org/JForum/posts/list/7965.page

Faces or icefaces does not automagically serialise or cache objects when sending it to the browser!
It converts to/from Strings if it can
and tries to waste as much of your time as possible if it can't!

So my fix was setting the selectItem's value to our DB Id in stead of the object,
using the Id property for the SelectOne value.
Then on partial submit when the setter gets called,
we have to iterate through the cached list to find the one matching the Id to set the real property.

<ice:selectOneMenu id="reportColumnIndex"
    value="#{scratchPad.reportColumnIndexId}"
    partialSubmit="true">
    <f:selectItems
        value="#{scratchPad.reportColumnIndexSelectItemList}" />
</ice:selectOneMenu>

Publish failed using Ant publisher - duplicate entry

2009-09-29T23:41:00.000+02:00

I got so frustrated this week with the eclipse + maven + glasfish combo.
It kept on refusing to publish my web project to glassfish with some lame excuse:

Publish failed using Ant publisher
  unable to assemble module
  duplicate entry: some.file

In any case I figured out a workaround (lucky guess):
Right-click on your project -> Maven -> Disable Workspace Resolution

Voi la. I can work again and debug my web apps.

rocketfuel-setup could not retrieve key

2009-08-26T02:10:00.000+02:00

I'd like to try out a in-house launchpad at some point,
so I thought I should get it.
But for some reason the rocketfuel-setup couldn't download
the keys it wanted for the dependencies it needed to apt-get:


Retrieving key 0A5174AF.
gpg: requesting key 0A5174AF from hkp server keyserver.ubuntu.com
gpgkeys: key 0A5174AF not found on keyserver
gpg: no valid OpenPGP data found.
gpg: Total number processed: 0
Could not retrieve key 0A5174AF.

So after mucking around trying to tell it to use my proxy,
I just commented out the relevant exit 1 lines.
This worked great, I just got prompted to confirm I want to install these packages.
I suppose the better solution would have been to try harder to manually install
the keys, but I didn't want to think about it too much.

how to use apt-key so apt-get stops complaining

2009-08-14T15:14:00.001+02:00

Use the last 8 digits apt-get gives you when it complains about keys eg.:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 5ADC2037

(I'm just pasting it here so I can find it again)

xfce=a new lease of life for my not-so-old laptop.

2009-08-09T01:00:00.000+02:00

Yes kde4 made my 64bit, 4GB mem, Core2 Duo 2.4GHz (kubuntu 9.04) laptop cry and die on me. For some reason it made X use a lot more memory than I would like.
So a couple of weeks ago I tried out xfce and I can be productive on it now. Although I miss a lot of features, at least I'm not running out of memory so easily and it does not crash so often anymore.
It may not strictly be Kde's fault, but by experimentation I found that xfce is better for me at the moment.

Yet another juicy Alfresco Labs 3.1 stacktrace...

2009-07-25T00:29:00.000+02:00

...which kept me busy for a couple of days.
I dumped it here for in case somebody else hits it.
So if you didn't find this post by googling an alfresco exception, you need to move along people, there is nothing to see here.

Without further ado, if you get the following exception:


javax.faces.FacesException: javax.faces.FacesException: Could not retrieve value of component with path : {Component-Path : [Class: javax.faces.component.UIViewRoot,ViewId: /jsp/dialog/container.jsp][Class: javax.faces.component.html.HtmlForm,Id: dialog][Class: javax.faces.component.UINamingContainer,Id: dialog-body][Class: org.alfresco.web.ui.common.component.UIPanel,Id: users-panel][Class: org.alfresco.web.ui.common.component.data.UIRichList,Id: users-list][Class: org.alfresco.web.ui.common.component.data.UIColumn,Id: _idJsp33][Class: javax.faces.component.html.HtmlOutputText,Id: _idJsp35]}
at org.apache.myfaces.context.servlet.ServletExternalContextImpl.dispatch(ServletExternalContextImpl.java:425)
at org.apache.myfaces.application.jsp.JspViewHandlerImpl.renderView(JspViewHandlerImpl.java:211)
at org.apache.myfaces.lifecycle.RenderResponseExecutor.execute(RenderResponseExecutor.java:41)
at org.apache.myfaces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:132)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:140)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.alfresco.web.app.servlet.AuthenticationFilter.doFilter(AuthenticationFilter.java:81)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)
Caused by: org.apache.jasper.JasperException: javax.faces.FacesException: Could not retrieve value of component with path : {Component-Path : [Class: javax.faces.component.UIViewRoot,ViewId: /jsp/dialog/container.jsp][Class: javax.faces.component.html.HtmlForm,Id: dialog][Class: javax.faces.component.UINamingContainer,Id: dialog-body][Class: org.alfresco.web.ui.common.component.UIPanel,Id: users-panel][Class: org.alfresco.web.ui.common.component.data.UIRichList,Id: users-list][Class: org.alfresco.web.ui.common.component.data.UIColumn,Id: _idJsp33][Class: javax.faces.component.html.HtmlOutputText,Id: _idJsp35]}
at org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:522)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:630)
at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:535)
at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:472)
at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:968)
at org.apache.jsp.jsp.dialog.container_jsp._jspService(container_jsp.java:637)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:630)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302)
at org.apache.myfaces.context.servlet.ServletExternalContextImpl.dispatch(ServletExternalContextImpl.java:419)
... 19 more
Caused by: javax.faces.FacesException: Could not retrieve value of component with path : {Component-Path : [Class: javax.faces.component.UIViewRoot,ViewId: /jsp/dialog/container.jsp][Class: javax.faces.component.html.HtmlForm,Id: dialog][Class: javax.faces.component.UINamingContainer,Id: dialog-body][Class: org.alfresco.web.ui.common.component.UIPanel,Id: users-panel][Class: org.alfresco.web.ui.common.component.data.UIRichList,Id: users-list][Class: org.alfresco.web.ui.common.component.data.UIColumn,Id: _idJsp33][Class: javax.faces.component.html.HtmlOutputText,Id: _idJsp35]}
at org.apache.myfaces.shared_impl.renderkit.RendererUtils.getStringValue(RendererUtils.java:227)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlTextRendererBase.renderOutput(HtmlTextRendererBase.java:69)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlTextRendererBase.encodeEnd(HtmlTextRendererBase.java:57)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:539)
at org.alfresco.web.ui.common.Utils.encodeRecursive(Utils.java:173)
at org.alfresco.web.ui.common.Utils.encodeRecursive(Utils.java:168)
at org.alfresco.web.ui.common.renderer.data.RichListRenderer$DetailsViewRenderer.renderListRow(RichListRenderer.java:292)
at org.alfresco.web.ui.common.renderer.data.RichListRenderer.encodeChildren(RichListRenderer.java:118)
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:527)
at javax.faces.webapp.UIComponentTag.encodeChildren(UIComponentTag.java:483)
at javax.faces.webapp.UIComponentTag.doEndTag(UIComponentTag.java:364)
at org.apache.jsp.jsp.users.users_jsp._jspx_meth_a_005frichList_005f0(users_jsp.java:659)
at org.apache.jsp.jsp.users.users_jsp._jspService(users_jsp.java:273)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
... 42 more
Caused by: javax.faces.el.EvaluationException: Cannot get value for expression '#{r.sizeLatest}'
at org.apache.myfaces.el.ValueBindingImpl.getValue(ValueBindingImpl.java:405)
at javax.faces.component.UIOutput.getValue(UIOutput.java:80)
at org.apache.myfaces.shared_impl.renderkit.RendererUtils.getStringValue(RendererUtils.java:223)
... 57 more
Caused by: javax.faces.el.EvaluationException: Exception getting value of property sizeLatest of base of type : org.alfresco.web.bean.repository.MapNode
at org.apache.myfaces.el.PropertyResolverImpl.getValue(PropertyResolverImpl.java:99)
at org.apache.myfaces.el.ELParserHelper$MyPropertySuffix.evaluate(ELParserHelper.java:535)
at org.apache.commons.el.ComplexValue.evaluate(ComplexValue.java:145)
at org.apache.myfaces.el.ValueBindingImpl.getValue(ValueBindingImpl.java:386)
... 59 more
Caused by: java.lang.NullPointerException
at java.io.StringReader.(StringReader.java:33)
at org.alfresco.repo.search.impl.lucene.ADMLuceneIndexerImpl.indexProperty(ADMLuceneIndexerImpl.java:1037)
at org.alfresco.repo.search.impl.lucene.ADMLuceneIndexerImpl.createDocuments(ADMLuceneIndexerImpl.java:606)
at org.alfresco.repo.search.impl.lucene.AbstractLuceneIndexerImpl.indexImpl(AbstractLuceneIndexerImpl.java:632)
at org.alfresco.repo.search.impl.lucene.AbstractLuceneIndexerImpl.indexImpl(AbstractLuceneIndexerImpl.java:657)
at org.alfresco.repo.search.impl.lucene.AbstractLuceneIndexerImpl.flushPending(AbstractLuceneIndexerImpl.java:789)
at org.alfresco.repo.search.impl.lucene.ADMLuceneIndexerImpl.doPrepare(ADMLuceneIndexerImpl.java:1591)
at org.alfresco.repo.search.impl.lucene.AbstractLuceneIndexerImpl.prepare(AbstractLuceneIndexerImpl.java:472)
at org.alfresco.repo.search.impl.lucene.AbstractLuceneIndexerAndSearcherFactory.prepare(AbstractLuceneIndexerAndSearcherFactory.java:783)
at org.alfresco.repo.transaction.AlfrescoTransactionSupport$TransactionSynchronizationImpl.beforeCommit(AlfrescoTransactionSupport.java:661)
at org.springframework.transaction.support.TransactionSynchronizationUtils.triggerBeforeCommit(TransactionSynchronizationUtils.java:48)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.triggerBeforeCommit(AbstractPlatformTransactionManager.java:835)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:645)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:632)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:314)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:117)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:166)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy176.getUserUsage(Unknown Source)
at org.alfresco.web.bean.users.UsersBeanProperties.getUserUsage(UsersBeanProperties.java:290)
at org.alfresco.web.bean.users.UsersDialog$1.get(UsersDialog.java:410)
at org.alfresco.web.bean.repository.QNameNodeMap.get(QNameNodeMap.java:117)
at org.alfresco.web.bean.repository.MapNode.get(MapNode.java:157)
at org.apache.myfaces.el.PropertyResolverImpl.getValue(PropertyResolverImpl.java:81)
... 62 more

nice, hey.

I think its reported here
https://issues.alfresco.com/jira/browse/ETHREEOH-1846

To fix it, I built a newer version of org.alfresco.repo.search.impl.lucene.ADMLuceneIndexerImpl from the svn sources, and dumped it in the alfresco/WEB-INF/classes and it works!

get rid of glassfish master password

2009-07-23T15:41:00.000+02:00

I've set up a webapp to be able to create-domain, deploy, test and delete-domain using the maven-glassfish-plugin.
The problem is that it insists on setting the master password.
Now its not possible to set the master password being used by the eclipse JavaEE glassfish plugin.
So when you try to start it from eclipse it asks for the master
password in the background:
Please enter the master password
After a while it times out and it says:
Server GlassFish at localhost failed to start.

I found out that you can tell glassfish to not ask the password anymore by doing:
asadmin change-master-password --savemasterpassword domain1
http://forums.java.net/jive/message.jspa?messageID=341172

However, I changed my admin password maven uses,
to be the real defaut master password: "changeit",
and now eclipse can start maven-created domains without me
having to --savemasterpassword
http://blogs.sun.com/alexismp/entry/what_is_a_glassfish_master

more alfresco pain

2009-07-21T21:24:00.000+02:00

This time I tried to send e-mails when new documents are added. I thought this would be simple. (With Alfresco labs 3.1)
First I got errors like:

20:08:32,529  ERROR [action.executer.MailActionExecuter]
Failed to send email to 'amanica@localhost'
as the address is incorrectly formatted

Eventually I figured out my test addresses are not acceptable to javamail. I had to setup amanica@localhost.dev before it worked.

Next I got the following:

20:08:33,310  ERROR [action.executer.MailActionExecuter]
Failed to send email to [root, test]
org.springframework.mail.MailPreparationException:
Could not prepare mail; nested exception is java.lang.NullPointerException
Caused by: java.lang.NullPointerException        
at com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:599)        
at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:388)        
at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:332)        
at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:347)        
at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:336)        
at org.alfresco.repo.action.executer.MailActionExecuter.executeImpl(MailActionExecuter.java:352

And I think setting a e-mail address for the admin user fixed that.

Thirdly it only wanted to send these rule e-mails from alfresco@alfresco.com, but if I copy slightly newer versions of
MailActionExecuter$1.class and MailActionExecuter.class into
${ALF_HOME}/tomcat/shared/classes/org/alfresco/repo/action/executer/
it works. I don't know if that breaks anything else in the process.

And finally, I'm still unhappy that they don't ship with oracle hibernate mapping files in the community edition, even in version 3.2 .

Caused by: java.lang.RuntimeException: Error occurred.  Cause: com.ibatis.common.xml.NodeletException: Error parsing XML.  Cause: java.lang.RuntimeException
: Error parsing XPath '/sqlMapConfig/sqlMap'.  Cause: com.ibatis.sqlmap.client.SqlMapException: The <sqlmap> resource is missing: alfresco/ibatis/#resource.
dialect#/content-insert-SqlMap.xml
     at org.alfresco.ibatis.HierarchicalSqlMapConfigParser.parse(HierarchicalSqlMapConfigParser.java:112)
     at org.alfresco.ibatis.HierarchicalSqlMapClientFactoryBean.buildSqlMapClient(HierarchicalSqlMapClientFactoryBean.java:86)
</sqlmap>

Like eclipse and maven, its painfull but theres nothing better :(

explore bazaar

2009-07-08T21:58:00.000+02:00

The up an coming bzr explorer is really promising to become: version control for human beings!

I tried to do a commit in it today and the following was very nice:

I can have the diff and the commit windows open simultaneously to be able to referback. (this was a problem before for me because both wants to lock to branch)
The auto-completion of words and filenames is awesome.

I tried to take a snapshot but [fn]+[prt_sc] launched infinite ksnapthots :( (but thats another story). After some reboots, I tried again:

trying to find related revisions is almost impossible on the commandline (i.e. it took too long), but its so nice with qlog.
The commit progress is also ultra cool

Wishlist:

Save draft commit messages eg. every 30 seconds (like gmail). Anything can happen while or after you typed the message and before you hit commit eg. a power failure.
In my case, my computer basically crashed when I tried to make a snapshot and it launched the infinite ksnapshots. (bonus points for a [save now] button!)
[esc] should close qdiff windows
qannotate
- ctrl+G should go to a line (like gannotate)
- ctrl+F should start a search (like gannotate)

So far I made an alias to be able to launch it while at the branch in a terminal:
alias be='bzr explore . &'
But I suspect I'll have a bzr explore icon on my application launcher soon.

Version control is getting so cool that I'm be tempted to quit coding and become a full-time version-controllist. :-P whooa endorphin rush..

eclipse galileo maven plugin

2009-06-29T18:35:00.000+02:00

I tried to install the maven plugin from http://m2eclipse.sonatype.org/update/ on the new eclipse today, but I got the following error:

Error unzipping org.maven.ide.components.maven_embedder Unexpected end of ZLIB input stream

Then I tried the dev version from http://m2eclipse.sonatype.org/update-dev/ and that seemed to work fine.

[edit 2009-07-15] Since then the dev version started spewing out null pointer exceptions when using the maven-assembly-plugin,
so I reverted back to the stable version and that seems to work now... Early adopters burn their fingers...

Split local/international network traffic between different adsl accounts on kubuntu.

2009-06-06T00:16:00.000+02:00

I was able to setup my internet on my laptop so that my local internet traffic gets charged at local rates (1/4 of the price for me).
This page helped me but it's a bit old and a little different to what I needed, so I thought I'll write down my steps (mostly copied and adjusted from said page).

My setup:
os = kubuntu 9.04 jaunty
isp = webafrica and I'm very happy with them
router = Mega 105 WR

Some tutorials say you need to change your router mode to be bridged, but I found out that mine is automatically in semi-bridge mode: I setup my main account on the router which can be used by all the computers in the house, but on my laptop I can setup an additional connection which gets bridged through the router.
sudo apt-get install ppp pppoeconf
(ppp includes rp-pppoe.so, which is installed manually by the original instructions, but I didn't have to since its in ppp)
Run pppoeconf
- Accept the defaults provided by pppoeconf and say yes to the start at boot option.
- I just answered yes to the "'noauth' and 'defaultroute'" question, since I changed it later in any case.
- It asks you for a username/password, this is your local adsl account authentication parameters as provided by your ISP.
- Now test the connection with sudo pon dsl-provider
- If you list the interfaces with ifconfig you should see ppp0 listed (and it should get an ip address).
- Disconnect ppp0 before continuing. sudo poff dsl-provider
Edit /etc/ppp/peers/dsl-provider by hand.
Only the parameters that you need to check are listed.
A hash before the line means the line is commented out.
sudo kate /etc/ppp/peers/dsl-provider
```
noipdefault
# defaultroute
# replacedefaultroute
# usepeerdns
```
So be sure that the above 3 parameters are commented out.
(We only want to use the DNS servers provided from the ISP from the international traffic.)
sudo kate /etc/network/interfaces
At the bottom of it you should have something like this:
```
manual ppp0
iface ppp0 inet ppp
provider dsl-provider
pre-up /sbin/ifconfig wlan0 up # line maintained by pppoeconf

#auto wlan0
#iface wlan0 inet manual
```
- I make ppp0 manual since I need to wait for my wireless lan to connect before I can connect to the local internet. With this I can have full control, which is good since I don't want to leave it on too long because you are directly on the internet now and you're router's firewall isn't protecting you from local traffic.
- I comment out the wlan0 section so that the network manager won't ignore it. You can remove it completely.
- Test the connections to make sure there are no problems.
  sudo ifup ppp0
  ifconfig should list ppp0
  sudo ifdown ppp0
Static routing
Now the fun part where we actually get the traffic flowing.
We need to tell the system to route all the South African traffic through the ppp0 interface instead of the wlan0 or eth0 interface.
We'll use static routing to do this.

Download Armin's list of local routes from http://alm.za.net/ip/localroutes4.txt
The list is updated every 24 hours and we'll use it instead of duplicating his work.
It contains all the network addresses that are specific to South Africa.
Save the file in /tmp and then move it to /etc/ppp/ :
sudo mv /tmp/localroutes4.txt /etc/ppp

We need to create a small script that tells the system to add the routes to the interface when if comes up.
Create a file in /etc/ppp/ip-up.d/ called "zanet".
sudo kate /etc/ppp/ip-up.d/zanet

Paste the following in the file :
```
#!/bin/sh -e
# Called when a new interface comes up

# add custom routing for zanet (local South Africa) on ppp0 device
if [ "$PPP_IFACE" = "ppp0" ]
then
cat /etc/ppp/localroutes4.txt | sed s/'\$LOCAL'/$PPP_IFACE/ | while read localroute
do
# Change net to host for /32 addresses
# This is a bug workaround - Armin must fix his list script.
if [[ $localroute =~ "/32" ]]
then
localroute=`echo $localroute | sed s/net/host/`
$localroute
else
$localroute
fi
done
fi

# We need to route DNS lookups via ppp0 (SAIX) instead of ppp1 (IS)
# The static routing will cause the DNS lookups to be made through the local IS
# connection and the SAIX network will block the lookups because they don't originate
# from their network.

#uncomment the following if you are using different isps:

#if [ "$PPP_IFACE" = "wlan0" ]
#then
#cat /etc/resolv.conf | sed s/nameserver// | sed s/' '// | while read nameserver
#do
#route add -host $nameserver $PPP_IFACE
#done
#fi
```
Make sure you can execute it:
```
sudo chmod a+x /etc/ppp/ip-up.d/zanet
```
Static routing should now work unless you made a mistake or I forgot something.
Test it by starting ppp0. (sudo ifup ppp0)
If you run route -n you should see huge list of static routes for the ppp0 interface and only a few when it is not started.

Automatic localroute updates
You could get wget to retrieve a new list of local routes every so often manually or with a cronjob. You can stick the following script in a executable file in /etc/cron.monthly/ eg. /etc/cron.monthly/update-local-routes:


#!/bin/bash

 cd /etc/ppp
 wget http://alm.za.net/ip/localroutes4.txt

 # If there is already a localroutes file replace it with the new one.
 if [ -f /etc/ppp/localroutes4.txt.1 ]
 then
 # Make sure that we didn't get an empty or nearly empty list
 # More than 1000 characters will qualify as a valid amount of local routes
 # Rather keep the old list if the new one is too small
 if [ `cat /etc/ppp/localroutes4.txt | wc -c` -gt 1000 ]
 then
 mv localroutes4.txt.1 localroutes4.txt
 fi
 fi

Make sure its executable:

sudo chmod a+x /etc/cron.monthly/update-local-routes

Lastly I use iftop -i ppp0 to monitor and make 100% sure where my traffic is being routed.

Howto setup up a queue in glassfish.

2009-06-04T13:18:00.000+02:00

This is my first attempt to setup queues on glassfish, so its probably not the best way, but its simple and it works for me for now.
Using the glassfish admin console:


* Configuration -> Java message Service -> Physical Destinations
  - [New]
  - Give it a name eg. my_test_queue and select queue.
  - [Ok]
* Resources -> JMS Resources -> Destination Resources
  - [New]
  - JNDI Name: queues/my_test_queue
  - Physical Destination Name: my_test_queue  (must be the name you set above)
  - Resource Type: javax.jms.Queue
  - [Ok]
* Resources -> JMS Resources -> Connection Factories
  (you only need one connection factory per type, not one per queue)
  - [New]
  - JNDI Name: connectionfactories/queueconnectionfactory
  - Resource Type: javax.jms.QueueConnectionFactory
  - [Ok]

Amarok 1.4 for me on Kubuntu Jaunty

2009-05-23T19:34:00.000+02:00

After playing a little with the new shiny Amarok 2 in Kubuntu 9.04,
I decided to go back to 1.4 for now.
I have been using Amarok to subscribe to podcast rss feeds
to download the latest episodes, and then to transcode
it to my ipod (it was a gift which I wasn't going to look in the mouth ok). This functionality did not seem to be in the shipped Amarok2 so I needed to go back.

Its quite easy to go back, just add the following source to your sources.list, update and install amarok14:
deb http://ppa.launchpad.net/bogdanb/ppa/ubuntu jaunty main

For more info see:
https://edge.launchpad.net/~bogdanb/+archive/ppa

Hibernate freeze

2009-05-20T14:16:00.000+02:00

All of a sunday my hibernate queries started to freeze when I try to run my unit tests at:

SocketInputStream.socketRead0(FileDescriptor, byte[], int, int, int) line: not available [native method]

Turns out I had the table or something locked in Sqldeveloper. I killed that session and everything started to work again.

Bazaar on sourceforge.net

2009-05-11T04:43:00.000+02:00

I've bean looking for a place to host a modular project which is being version controlled with Bazaar. I would have loved to use Launchpad, but I can't because of the following:

Launchpad only allows one level of branches (no hierarchy). My project is made up of a lots of sub-projects: I have a main branch which controls the sub-projects as bzr-externals.
Launchpad does not have a nice project wiki or any custom web content.

I saw that sourceforge.net now supports Bazaar, but I was a bit worried when I saw on their wiki that they only support Bazaar version 1.10 . It turns out that it is thankfully only an outdated doc:

[me@shell-21002 ~]$ bzr --version
Bazaar (bzr) 2.1.1
Python interpreter: /usr/bin/python 2.4.3
Python standard library: /usr/lib64/python2.4
Platform: Linux-2.6.18-...

(I don't seem to have rights to correct the wiki and I could not google the current version, so I'm documenting it here for you.)

I did test that I could upload nested branches. But unfortunately the code browsing tool on Sourceforge (loggerhead) does not display the nested branches :( Hopefully that is fixable..

Word of the week: Slack

2009-04-16T23:32:00.001+02:00

This one was inspired by my friend Richard Kolb's favorite distro: http://www.slackware.com/
which by the way has a new South-african derivative: http://www.kongoni.co.za/
This may not be that informative, but its still fun to call slackware lazy, weak, tardy, late, idle, quiet and slowing :)

slack

–adjective

1.	not tight, taut, firm, or tense; loose: a slack rope.

2.	negligent; careless; remiss: slack proofreading.

3.	slow, sluggish, or indolent: He is slack in answering letters.

4.	not active or busy; dull; not brisk: the slack season in an industry.

5.	moving very slowly, as the tide, wind, or water.

6.	weak; lax.

7.	Nautical. easy (def. 15a).

–adverb

8.	in a slack manner.

–noun

9.	a slack condition or part.

10.	the part of a rope, sail, or the like, that hangs loose, without strain upon it.

11.	a decrease in activity, as in business or work: a sudden slack in output.

12.	a period of decreased activity.

13.	Geography. a cessation in a strong flow, as of a current at its turn.

14.	a depression between hills, in a hillside, or in the land surface.

15.	Prosody. (in sprung rhythm) the unaccented syllable or syllables.

16.	British Dialect. a morass; marshy ground; a hollow or dell with soft, wet ground at the bottom.

–verb (used with object)

17.	to be remiss in respect to (some matter, duty, right, etc.); shirk; leave undone: He slacked the most important part.

18.	to make or allow to become less active, vigorous, intense, etc.; relax (efforts, labor, speed, etc.); lessen; moderate (often fol. by up).

19.	to make loose, or less tense or taut, as a rope; loosen (often fol. by off or out).

20.	to slake (lime).

–verb (used without object)

21.	to be remiss; shirk one's duty or part.

22.	to become less active, vigorous, rapid, etc. (often fol. by up): Business is slacking up.

23.	to become less tense or taut, as a rope; to ease off.

24.	to become slaked, as lime.

—Idiom

25.

take up the slack,

a.	to pull in or make taut a loose section of a rope, line, wire, etc.: Take up the slack before releasing the kite.

b.	to provide or compensate for something that is missing or incomplete: New sources of oil will take up the slack resulting from the embargo.

Origin:
bef. 900; ME slac (adj.), OE sleac, slæc; c. ON slakr, OHG slach, L laxus lax

Related forms:

slack⋅ing⋅ly, adverb

slackly, adverb

slackness, noun

Synonyms:
1. relaxed. 2. lazy, weak. 3. dilatory, tardy, late. 4. idle, quiet. 11. slowing, relaxation. 17. neglect. 18. reduce, slacken. 21. malinger.

http://dictionary.reference.com/search?q=slack

sweet ubuntu commandline network trafic monitor

2009-04-16T11:43:00.002+02:00

sudo apt-get install iftop
sudo iftop -Bp

I looked at the other recommendations at:
http://ubuntuforums.org/showthread.php?t=965242
but I thing I prefer iftop at the moment.

I wish I could see which processes are using the bandwidth,
but that would probably involve a lot of magic.

Alfresco pain

2009-04-14T13:24:00.010+02:00

After struggling a lot, I finally got Alfresco running on my Glassfish (v2ur2-b04),
for a couple of minutes then it broke again. I'll update this if I get it working one day.

First of all, look at the following for how to install using an oracle db.
http://wiki.alfresco.com/wiki/Database_Configuration
Which worked mostly, except it seems like you have to use the AlfrescoOracle9Dialect eg.:

hibernate.dialect=org.alfresco.repo.domain.hibernate.dialect.AlfrescoOracle9Dialect

Initially I got the following exceptions:

Invocation of init method failed; nested exception is java.lang.NoSuchMethodError: org.objectweb.asm.ClassWriter.(Z)V
Caused by: java.lang.NoSuchMethodError: org.objectweb.asm.ClassWriter.

and

Invocation of init method failed; nested exception is java.lang.NoSuchMethodError: org.objectweb.asm.ClassVisitor.visit(IILjava/lang/String;Lj
ava/lang/String;Ljava/lang/String;[Ljava/lang/String;)V
Caused by: java.lang.NoSuchMethodError: org.objectweb.asm.ClassVisitor.visit

This was fixed by putting the correct hibernate jars in the domain1/lib and domain1/lib/ext folders.
I put asm-attrs.jar, cglib-2.1.3.jar, ojdbc14_g.jar (for oracle) in domain1/lib and
asm.jar, serializer.jar, xalan.jar in domain1/lib/ext

Next when I tried to log into the share webapp, I got the following:
"The remote server may be unavailable or your authentication details have not been recognized."
Thanks to the following link I figured out that alfresco does not like to run on a different port the server port is hardcoded into the war files in several places:
http://forums.alfresco.com/en/viewtopic.php?f=8&t=13625&start=15&st=0&sk=t&sd=a&hilit=The+remote+server+may+be+unavailable+or+your+authentication+details+have+not+been+recognised#p45826

Since I'd like to run it on a non-default port, I updated the port number by replacing all occurrences of 8080 with 12080.

I'm lazy so I did it like this:

$ cd domain1
$ replace 8080 12080 -- `find -iname "*.wsdl"`
$ replace 8080 12080 -- `find -iname "*.xml"`
$ replace 8080 12080 -- `find -iname "*.ftl"`

(btw this replace command I used is part of mysql-server-5.0: /usr/bin/replace)
See http://wiki.alfresco.com/wiki/Changing_Default_Port_Configuration for more info.

Next I got this exception in my logs:
org.alfresco.web.framework.exception.RendererExecutionException: Unable to execute 'body' JSP include: /site-index.jsp
Caused by: java.lang.ClassCastException: org.alfresco.tools.FakeHttpServletResponse cannot be cast to org.apache.coyote.tomcat5.CoyoteResponseFacade

I found a fixed up version of alfresco-web-framework.jar which goes in domain1/applications/j2ee-modules/share/WEB-INF/lib on this forum:
http://forums.java.net/jive/thread.jspa?threadID=58906
Now I could actually log in.

But somewere along the line I got the following:

org.alfresco.web.framework.exception.RendererExecutionException: FreemarkerProcessor failed to process template: org/alfresco/global/slingshot-login.ftl

Caused by: freemarker.core.InvalidReferenceException: on line 32, column 70 in org/alfresco/global/slingshot-login.ftl link not found.

on line 32, column 70 in org/alfresco/global/slingshot-login.ftl link not found.
The problematic instruction:
----------
==> user-directive link [on line 32, column 70 in org/alfresco/global/slingshot-login.ftl]
in user-directive template.body [on line 6, column 1 in org/alfresco/global/slingshot-login.ftl]

and what fixed it for me AFAICT is to add the sun-web.xml described here:
http://blogs.sun.com/mandy/entry/alfresco_on_glassfish_short_version

mm.. seems like everything is not working for me yet. I have to switch between the patched and the original versions of alfresco-web-framework.jar (i.e log in with the one and play further with the other)

I'm doing a svn checkout at the moment to see if the developent verion works better on glassfish.
Maybe I can submit some patches if necessary.

Looking for unread gmail

2009-04-08T13:27:00.003+02:00

I was trying to get look at only my unread e-mail under a particular label. It turns out you can search your mail with is:unread

There are other tricks too, have a look at this:
https://mail.google.com/support/bin/answer.py?answer=7190

Jaunty Jackalope (Ubuntu 9.04) is coming soon

2009-04-08T13:04:00.002+02:00

It is expected to be released on the 23rd of April 2009.

&amp;lt;a href="http://www.ubuntu.com/"&amp;gt;&amp;lt;img src="http://www.ubuntu.com/files/countdown/904/countdown-9.04-1/00.png" alt="Ubuntu 9.04 - on desktops, netbooks, servers and in the cloud" width="180" height="150" border="0" /&amp;gt;&amp;lt;/a&amp;gt;

Put persistence.xml in the war

2009-03-17T19:34:00.005+02:00

I've been trying for days to get jpa, jndi, glassfish, hibernate and oracle to play together.

The main problem turns out that you have to put the persistence.xml file in your war file (project/web-root/WEB-INF/src/META-INF) not in your jar file.
I'll probably investigate more to see if it is somehow possible to put it in the jar, but for now my problems are solved.

... after some further experimentation I was able to put it in the jar, but I'm using <mapping-file>xx_orm.xml</mapping-file> now.

No PasswordCredential found

2009-02-14T03:01:00.003+02:00

I got the exception below while trying to set up a JNDI database configuration in glasshish to point to my local Oracle XE installation. Google didn't help so I'm posting it here for in case it happens to me again.
I didn't actually figure out how to resolve it. I fiddled around in domains/domain1/config/domain.xml a little, but in the end I think restarting Glassfish did the trick for me.


INFO: RAR7099: The mcf being used to allocate the connection and the MCF in the pool are not equal.
WARNING: RAR5038:Unexpected exception while creating resource for pool aum_pool. Exception : No PasswordCredential found
WARNING: RAR5117 : Failed to obtain/create connection from connection pool [ aum_pool ]. Reason : No PasswordCredential found
WARNING: RAR5114 : Error allocating connection : [Error in allocating a connection. Cause: No PasswordCredential found]
WARNING: java.sql.SQLException: Error in allocating a connection. Cause: No PasswordCredential found
at com.sun.gjc.spi.base.DataSource.getConnection(DataSource.java:115)

Eclipse Dynamic Web Project + Maven2 = initial pain

2009-02-13T00:19:00.006+02:00

Eclipse 3.4 ganymede gave me a VERY frustrated day yet again :(
I spent most of the day convincing it to to install the m2eclipse plugin.
It kept on telling me:

No repository found containing: org.maven.ide.components.dependency_tree/osgi.bundle

So after updating all my eclipse plugins and also using the Maven Integration for Eclipse Dev Update Site and restarting Eclipse, it finally decided it will install.
(You almost want to swear at it and call it M$ Eclipse. Ok it wasn't that bad.)

Next I came to a painful catch 22: I want a Dynamic Web Project so that my code can be automatically deployed on my Glassfish server. But I also want it to be a Maven project for all the maven goodness, without changing the standard maven code layout.

I googled for hours but I only found my worst fear to be true: The only way to do it is to make it a web project, changing its structure to be in the maven layout and then activate it as a maven project. I improved on this site's methods a bit by doing some configs up front and thus avoiding to mess with them later. Here are my steps as good as I remembered:

(I created a reference maven web project in eclipse, but it turned out that I didn't actually need it)
Create a new Eclipse Dynamic Web Project. Don't click finish, click [next].
Set the 'Content Directory' to 'src/main/webapp' and the 'Java Source Directory' to 'src/main/java'. Now you can click [finish].
Right click on the project -> Maven -> Enable Dependancy Management.
Set the packaging to war, [finish].
You can delete the build folder now since maven already started to use the target folder.
If you need the other standard maven source and target folers, you can add them manually or directly in .classpath:
<classpathentry kind="src" path="src/main/resources">
<classpathentry kind="src" output="target/test-classes"
path="src/test/java">
<classpathentry kind="src" output="target/test-classes"
path="src/test/resources">
From there I just had to set maven to use Java6 in pom.xml:
<build>
<pluginmanagement>
<plugins>
<plugin>
<groupid>org.apache.maven.plugins</groupid>
<artifactid>maven-compiler-plugin</artifactid>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</pluginmanagement>
</build>
Right click on the project -> Maven -> Update Dependancies.

I removed the following from .settings/org.eclipse.wst.common.component:

<wb-resource deploy-path="/WEB-INF/classes" source-path="/src/test/java"/>
<wb-resource deploy-path="/WEB-INF/classes" source-path="/src/test/resources"/>

Then I could run maven tasks and also deploy it to my glassfish server (already set up to be managed by eclipse the normal JavaEE way (run as -> run on server))

sweetness! I love Eclipse+JavaEE+maven again.
I think the WTP or whatever does the new 'Dynamic Web Project' wizard would do well to have a checkbox which can setup the web project in the maven sturcture for you.
tomorrow (aka later today) I have to do the real work of actually putting an application into this empty shell.

goodnight

Putting God first.

2009-01-25T10:36:00.004+02:00

Putting God first is my other new-years resolution/calling for 2009.
I believe God is telling me the first step towards that is to start
spending some time with Him and His Word in the mornings.
I'm not a morning person so this is hard.

I found this Psalm very inspiring, especially verses 2 and 8:

--
Psalm 101

A Psalm by David.

{101:1} I will sing of loving kindness and justice.
To you, Yahweh, I will sing praises.
{101:2} I will be careful to live a blameless life.
When will you come to me?
I will walk within my house with a blameless heart.
{101:3} I will set no vile thing before my eyes.
I hate the deeds of faithless men.
They will not cling to me.
{101:4} A perverse heart will be far from me.
I will have nothing to do with evil.
{101:5} I will silence whoever secretly slanders his neighbor.
I won't tolerate one who is haughty and conceited.
{101:6} My eyes will be on the faithful of the land,
that they may dwell with me.
He who walks in a perfect way,
he will serve me.
{101:7} He who practices deceit won't dwell within my house.
He who speaks falsehood won't be established before my eyes.
{101:8} Morning by morning, I will destroy all the wicked of the land;
to cut off all the workers of iniquity from Yahweh's city.

(from the World English Bible: http://ebible.org/ )

--
it is time to seek Yahweh, until he comes and rains righteousness on you. - Hosea 10:12

--
Or don’t you know that your body is a temple of the Holy Spirit which is in you, which you have from God? You are not your own, for you were bought with a price. Therefore glorify God in your body and in your spirit, which are God’s.
1 Corinthians 6:19-20

vsftp is reporting times as GMT

2009-01-16T14:31:00.003+02:00

It has baffled me for days that my ftp (vsftp) server shows
file timestamps in the wrong timezone: UTC
After some searching I found that there is a hidden option
for setting it.
(it isn't in the default config file /etc/vsftpd.conf)

Q) Help! vsftpd is reporting times as GMT times and not local times!
A) This behaviour can be changed with the setting "use_localtime=YES

After adding that to the end of /etc/vsftpd.conf, and doing:
sudo /etc/init.d/vsftpd restart

it works now!
Now why isn't this the default???
http://www.flux.org/pipermail/linux/2004-June/015484.html
http://vsftpd.beasts.org/vsftpd_conf.html

This got me thinking is it some sort of a standard that ftp servers return timestamps in utc?

colemak

2008-12-21T14:59:00.003+02:00

I have some time off from work and decided it is time to
finally learn and use the colemak keyboard layout.
This is one of my new year resolutions, and I cannot
explain how exited I am about this. I'm actually typing
this post using it, but its still slow going.

I had some trouble getting it to work in ktouch, but I figured it out:
http://forum.colemak.com/viewtopic.php?pid=4378#p4378

I also had some trouble convincing kubuntu to handle the capslock key
as a backspace key. The final solution for me was to make a little script,
and get it to run when kde starts up.
script:

#!/bin/bash

#setup capslock -> backspace (nice for colemak)
xmodmap -e "remove Lock = Caps_Lock"
xset r 66

run it automatically:
system settings -> advanced -> autostart

I practised for 30-45 minutes per day and I learn more keys every day.
Some of the nice things about Colemak for me are:

You learn the common keys first, so you can actually start typing quite soon. (You can type a lot by just using the home row.)
You are forced to touchtype, because looking at the keyboard doesn't help (assuming you didn't swap your keys, which I recommend.)
Most of your short cut keys are in the same position.

I found these finger stretches quite handy:

Symbolic link not allowed

2008-12-11T01:42:00.002+02:00

I got the following nasty exception in my /var/log/apache2/error_log,
and it took me too long to figure out how to fix it:

Symbolic link not allowed or link target not accessible: /opt/gforge5/plugins/scmbzr

Where in my case /opt/gforge5/plugins/scmbzr is a symlink to somewhere else.
I checked and rechecked all my permissions, but nothing worked.

So eventually it turns out that for every directory in the path where you have symlinks, you need something like:


<directory>
    Options FollowSymLinks
</directory>

(because I have a symlink in plugins called scmbzr)

Thanks a LOT to Ivan Van Laningham who mentioned this on some mailinglist:
http://www.mail-archive.com/mailman-users@python.org/msg44430.html

A query which generates a sequence in Oracle

2008-12-08T09:34:00.002+02:00

Sometimes for some reason, you may need a query in Oracle
which can generate a sequence of numbers or dates.
I found the following to be an elegant way of doing it:

--count from 1 to 10
SELECT rownum
FROM dual
CONNECT BY LEVEL <= 10

--even numbers from from 2 to 20
SELECT rownum*2
FROM dual
CONNECT BY LEVEL <= 10

--get the previous 100 days
SELECT trunc(sysdate) - rownum day
FROM dual
CONNECT BY LEVEL <= 100

Whoohoo, I'm a hero today!

2008-12-04T14:42:00.007+02:00

In order to answer somebody's question today,
I figured out how to use bzr replay
this made me his hero for a day,
and this in turn has made *my* day!

https://answers.edge.launchpad.net/bzr/+question/53349
Markus Korn confirmed that the question is solved:
Thanks a lot Marius, this initial commit did the trick,
you are my hero of the day ;)

oracle XE sessions and processes

2008-12-03T23:00:00.002+02:00

I found that my locally installed Oracle XE runs out of available connections far too soon for a php app I'm running. This results in some weird gui behaviour: some frames just don't load. Fortunately I found a way to sort of makes it a little better:

sqlplus system@XE
show parameters sessions;
alter system set sessions=250 
 scope=spfile;
show parameters processes;
alter system set processes=200
 scope=spfile;
sudo /etc/init.d/oracle-xe restart

http://www.markcallen.com/oracle/oracle-xe-tuning

kubuntu intrepid automount external harddrive

2008-11-22T00:08:00.005+02:00

The new intrepid kubuntu comes with a nice plasmoid where mountable partitions show up wehen you plug in USB flash disks and external hard drives.
The problem is, they don't get mounted automatically, which is what I want (to streamline my backup process). Fortunitely I found this thread which gave me a hint:
http://kubuntuforums.net/forums/index.php?topic=3098289.0

I first tried to download and build devicenotifier_automount from sources, but then after downloading a ton of -dev packages etc. and still not getting it to build, it dawned on me to look for a PPA. I found one:
https://launchpad.net/~samrog131/+archive
I've installed it successfully but haven't restarted X & tested yet.
Edit: so it seems you don't need to restart X, just use the `New Device Notifier Automount` plasmoid. Works great so far (2 minutes of testing:)

bash echo on

2008-11-22T00:04:00.002+02:00

I've searched previously for a way to echo all the commands in a bash script.
Today i found it on a asp page of all places:

set -o verbose #echo on
set +o verbose #echo off

If you want to do it once to debug a script you can also do:
bash -x your_script.sh

some words of the day

2008-11-20T01:17:00.005+02:00

I regularly send out a word of the day/week/month, so I decided to also publish them on my blog from now on. So without some further ado, here is the some of all:

somebodies
somebody
someday
somehow
someone
someones
someplace
something
somethings
sometime
sometimes
someway
someways
somewhat
somewhats
somewhere
somewheres
and of course my favourite: somesuch!

There you have it: all the words starting with some except the ones starting with somer. Like me, I know you always wanted to know that.
This list was compiled using the linux command `look some`.
This post was inspired by my friend Sizwe Mabanga's saying: "Someway Somehow".

gdebi

2008-11-18T15:20:00.002+02:00

Have you ever downloaded a .deb file and wondered what the best way to install it is?
This little gem of an app, does the trick for me. It installs the file while resolving and installing all its dependencies!

gdebi is a simple tool to install deb files. It lets you install local deb packages resolving and installing its dependencies.

apt does the same, but only for remote (http, ftp)
located packages.

It has a graphical user interface but can be used in your terminal.

https://launchpad.net/gdebi

kdirstat

2008-11-12T13:53:00.003+02:00

I recently went over to Kubuntu 8.10 (Intrepid), and I'm trying to get used to dolphin now. But it doesnt have the super cool "file size view" which I used to love in konqueror.
The soloution is to install kdirstat, which pretty much has the same functionality.
(Found it on http://sathyasays.com/2008/03/19/find-out-how-much-space-each-file-is-occupying/)

http://kdirstat.sourceforge.net/

java.net.SocketException: Too many open files

2008-11-12T12:23:00.003+02:00

We hit this again on sles today, so I thought I should leave a note here for posterity.
java.io.FileNotFoundException: /home/tcmas/tomcat/5.0.28/work/Catalina/localhost/balancer/SESSIONS.ser (Too many open files)

It might be caused by the small amount of memory available! so increasing that, may fix it.
It may also be the the number of open files limit on linux:

Increase file descriptor limit under Linux to prevent java.net.SocketException: Too many open files
Get current limit:
ulimit -n
cat /proc/sys/fs/file-nr
The default limit is 1024.
Get current number of open file descriptors:
lsof [-p pid] | wc -l
Increase the limit:
Edit /etc/security/limits.conf:
username hard nofile 32768

http://hausheer.osola.com/docs/11

nls_lang.sh: 114: [[: not found (Oracle XE problem on ubuntu)

2008-11-10T17:22:00.004+02:00

I installed Oracle Express edition on Kubuntu again, and I got a familiar error again after running:
. /usr/lib/oracle/xe/app/oracle/product/10.2.0/server/bin/oracle_env.sh
/usr/lib/oracle/xe/app/oracle/product/10.2.0/server/bin/nls_lang.sh: 114: [[: not found

the solution is to change (as root or sudo) the first line in the "nls_lang.sh" from
#! /bin/sh
to
#! /bin/bash

http://forums.oracle.com/forums/thread.jspa?messageID=2325040

Figured out how to save my kde4 session

2008-11-08T22:54:00.002+02:00

just run:

dbus-send --dest=org.kde.ksmserver /KSMServer org.kde.KSMServerInterface.saveCurrentSession

http://raetsel.wordpress.com/2008/04/25/kde4-save-current-session-dbus-to-the-rescue/

For some reason my HP laptop crashes from time to time, and then my session disappears :'(

knetstats

2008-11-07T21:30:00.002+02:00

I found this gem of an app a while ago, for monitoring the current network usage.
After installing intrepid, I had to look for it again, so here's the link
http://knetstats.sourceforge.net

How I got php with oci8 working

2008-10-24T00:59:00.010+02:00

Install Oracle instant client (the basic package and the SDK!). (You obviously need the 64bit version on a 64bit architecture). I tried doing this using my locally installed oracle express edition (XE) but that whas a whole lot of pain:
OCIEnvNlsCreate() failed. There is something wrong with your system - please check that ORACLE_HOME is set and points to the right directory
I ended up using oracle_instantclient_10_2 which worked!!
sudo -i
apt-get install apache2 php5 php5-dev php-pear libaio1
Make sure your $ORACLE_HOME and $LD_LIBRARY_PATH is set. Since I have 2 different versions of 'oracle' I set these two variables in /usr/sbin/apache2ctl, at the top of the 'CONFIGURATION SETION':
export ORACLE_HOME=/stuph/install/oracle_instantclient_10_2
export LD_LIBRARY_PATH=$ORACLE_HOME
```
echo $ORACLE_HOME >> /etc/ld.so.conf
```
```
ldconfig
```
Check if the symlinks named libclntsh.so and libocci.so exist in $ORACLE_HOME, which we will need later. In my case these symlinks were not created by ldconfig, so I created them manually:
ln -s libclntsh.so.11.1 libclntsh.so; ln -s libocci.so.11.1 libocci.so
pecl install oci8
To enable the oci8 module, add "extension=oci8.so" to /etc/php5/apache2/php.ini and /etc/php5/cli/php.ini). (put this line after the examples starting with ; in the "Dynamic Extensions" section).
```
ldconfig
```

apache2ctl restart

(or

/etc/init.d/apache2 force-reload

to make sure)

You should see the oci8 module in the output of phpinfo(). (put info.php in ~www-data or ~apache with the following content and browse to it: "<? phpinfo() ?>")

(I'm sorry if this assumes you know how to do certain stuff, but this is a howto for myself, so that I can remember how to do this in a mounth's time)

my bash setup

2008-10-11T15:30:00.000+02:00

Here are some things I put in ~/.bashrc or /etc/bash.bashrc to make my life easier:

# When using bash, I use ctrl+r a lot to find commands I executed recently.
# I found that I remember my commands for much longer than bash does,
# so I increased my bash's memory:
export HISTFILESIZE=3000 # the bash history should save 3000 commands
export HISTCONTROL=ignoredups # don't put duplicate lines in the history.
export HISTCONTROL=ignoreboth # ignore same sucessive entries.
# (from http://www.novell.com/coolsolutions/tools/17142.html)

# I like to have a colour prompt with my user, the machine I'm on and the full
# path. Its a bit long so I put it on 2 lines.
PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;33m\]\w\[\033[00m\]>\n\$ '

# enable bzr command auto completion
. /opt/bzr/bzr.current/contrib/bash/bzr.simple

# bzr aliasses
alias bt='./bzr --no-plugins selftest'
alias bd='bzr diff'
alias bl='bzr log'
alias bp='bzr pull -v |less'
alias bm='bzr missing |less'
alias bs='bzr status'

# bzr functions, which cant be done by alias or bzr's alias
bh(){
#the $@ inserts all the parameters you pass in
bzr help "$@" |less
}

bcd(){
bzr cdiff "$@" | less -R
}

Super cool startup script for linux

2008-10-05T15:03:00.000+02:00

I recently had to get a startup script going which works on Ubuntu and Sles for loggerhead. I came up with these install instructions and following simple but super cool init script. Note that this should work for basically any linux daemon, you just need to rename the script (loggerheadd) and change the script a little.

Copy loggerheadd to /etc/init.d
Edit the file to configure it.
Register the service:
cd /etc/init.d

on upstart based systems like Ubuntu run:
update-rc.d loggerheadd defaults

on Sysvinit based systems like Centos or SuSE run:
chkconfig --add loggerheadd

Here follows the script (the indentation is a bit messed up by blogspot)

#!/bin/sh
### BEGIN INIT INFO
# Required-Start: $local_fs $remote_fs $network
# Default-Start: 3 5
# Default-Stop: 0 1 2 6
# Short-Description: Loggerhead
# Description: Manage Loggerhead (a web viewer for projects in bazaar)
### END INIT INFO

# Configure this please: #
LOGGERHEAD_PATH=/opt/loggerhead
LOG_FOLDER=/var/log/loggerhead
LOG_FILE=$LOG_FOLDER/loggerheadd.log
PREFIX=/loggerhead
PORT=8080

# You can add additional options to serve-branches here:
START_CMD="$LOGGERHEAD_PATH/serve-branches --prefix=$PREFIX --log-folder=$LOG_FOLDER --port=$PORT /var/lib/gforge/bzrroot/"

#
# main part
#
case "$1" in
start)
python $START_CMD > $LOG_FILE 2>&1 &
echo "Started loggerhead. (See $LOG_FOLDER for details.)"
;;
stop)
pkill -f "$START_CMD"
;;
status)
proccess=`pgrep -fl "$START_CMD"`
echo "$proccess"
netstat -anp |grep -e ":$PORT"
if [ -z "$proccess" ]; then
echo "Loggerhead is not running."
else
echo "Loggerhead is running."
fi
;;

*)
echo "Usage: loggerheadd { start | stop | status }"
exit 1
esac

Maximum file sizes on differrent file systems

2008-10-01T10:58:00.000+02:00

I was looking up the maximum file size on a file system for a friend, and I realised I didn't even know this stuff. Here is a couple:
FAT32: 4 GiB
NTFS: 16 EiB
ext2 and ext3: 16 GiB to 2 TiB (see this note about max range)
ext4: 1 EiB
ReiserFS: 8 TiB
HFS plus (used by Apple's Mac OS X): 8 EiB

http://en.wikipedia.org/wiki/Comparison_of_file_systems#Limits

Set partition labels on linux.

2008-09-14T10:53:00.000+02:00

My colleague Elardus complained that my flash drive didn't have volume labels set and I also wanted automounting to make a nice consistant mountpoint eg. /media/my_flash_drive.
I didn't think think it would be that hard, I really thought that a gui like gparted or qtparted would be able to do that, but was disappointed. So I had to do it from the commandline.

To set the label for ext2 or ext3 partitions:

sudo e2label /dev/sdb2 new_label

where /dev/sdb2 is the partition you want to label. (To get a list of mounted partitions you can do `df -ahT`)

For FAT partitions you first need to configure the drive:
you have to edit /etc/mtools.conf, make f: drive be /dev/sdb1

sudo mlabel f:new_label

Initially I got the following error.

Total number of sectors (256976) not a multiple of sectors per track (63)!
Add mtools_skip_check=1 to your .mtoolsrc file to skip this test

I just did what it asked and then it worked:

echo "mtools_skip_check=1" > ~/.mtoolsrc

I found my info on this page:
http://fedoraforum.org/forum/archive/index.php/t-86378.html

Laptop tip of the day.

2008-09-12T00:56:00.000+02:00

If you easily get cold feet,
I want to tell you something neat.
Put your toes on a transformer
it'll make your feet warmer.
AC to DC gives off some heat!

:)
ok I wrote it at 1:00 AM
(with my toes on the ... you guessed it)

European experience

2008-09-10T08:36:00.000+02:00

My wife and I recently returned from a tour of Europe (2008-08-08..2008-08-24) and I just want to make you guys a little jealous.
We decided earlier this year that we should probably see a bit of the world before the kids arrived and I thought
Europe is a nice diverse, architecturally and historically rich place to go.
We had to organise it pretty quickly since my wife is sort of forced to be on leave in august (private school holidays),
which worked out to be a fairly quite time with regards to projects at work.

Without going into too much detail, we first flew to Dubai and after a 2 hour stop over,
we flew to London. There we stayed over one night and then embarked on our Trafalgar tour, which I must say
was extremely well organised, we had the best driver and tour director ever!
During our tour we slept over in Amsterdam (Netherlands), Ludwigshafen (Germany), Innsbruck (Austria),
Venice, Rome, Florence (Italy), Stans (Next to lake Luzern, Switserland), Paris (France :) .
We drove mostly by bus and had lots of interesting outings at the places we passed by.
After the tour we had two nights in London again, where we saw most tourist sights using the tourist buses.
Finally we had a night in Dubai where we also had a short Arabian Adventure, which was also extreamly well organised and very nice.

On this trip we did aeroplanes, big boats (ferries), medium boats, little boats (including gondolas), big buses, little buses, a train, a mono rail, a cog rail and cable cars (big and small),
we walked quite a lot too (I got some blisters even), but we didn't do any cars.
We saw lots of old and new buildings, a lot of country side and a lot of famous attractions.
The places we visited had way more water than what we are used to, a lot of towns have BIG rivers running through the middle.
We made great friends and met people from all over the word, where the most of the tour group was from Australia.

This was deffinitely a worthwhile and value for money experience, which I can highly reccomend (even though the pound and euro is so much stronger than the rand).

For some photos, checkout:
http://picasaweb.google.com/amanic/EuropeanExperience

From European Experience

Headless VirtualBox in ubuntu server.

2008-08-06T19:04:00.000+02:00

1) I tried to get a headless VirtualBox running in the virtualbox which I could apt-get from a standard Ubuntu Hardy repository. - turns out that that version of virtual box does not support headless mode.

2) Then I tried to install a version of virtualbox I downloaded previously from sun (virtualbox_1.6.2-31466_Ubuntu_hardy_i386.deb) but it failed to compile its kernel module, even after I installed the kernel source:

# /etc/init.d/vboxdrv setup
* Stopping VirtualBox kernel module
* done.
* Removing old VirtualBox kernel module
* done.
* Recompiling VirtualBox kernel module
* Look at /var/log/vbox-install.log to find out what went wrong

3) Then I downloaded the latest version from sun, installed it:

# gdebi virtualbox_1.6.4-33808_Ubuntu_hardy_i386.deb

and it worked beautifully!

maven repository manager

2008-08-01T18:21:00.000+02:00

After struggling for a couple of days, I finally managed to set up a local maven repository behind a proxy.

I first tried nexus, but it's configuration is very buggy and despite the fact that it don't work for me, it keeps on forgetting my settings if I open on it again.
Then I tried artifactory, ant it too looked promising, but for some reason I could not get it to download stuff through a proxy either. To be fair after I figured out that my real problem as that my maven clean plugin was broken, I managed to get artifactory working through a proxy (but I think I like archiva the most at the moment).
Then I tried apache archiva, which looked even more promising since it actually had the concept of a network proxy on its configuration screen. After a lot of googling, I found out that its a known (and fixed but un-released) bug in archiva 1.1. (http://jira.codehaus.org/browse/MRM-884). So I installed version 1.0.2 and my downloads began to work!!

The only problem was that as part of testing if this works, I deleted the org directory in my maven repository (as described in the nexus section of the maven difinitve guide).
This caused my `mvn clean` to stop working:
"org.apache.maven.plugin.version.PluginVersionNotFoundException: The plugin 'org.apache.maven.plugins:maven-clean-plugin' does not exist or no valid version could be found"
After a bit of googling I found out that deleting my repository (~/.m2/repository) fixes this problem!
(http://www.mail-archive.com/users@maven.apache.org/msg68288.html)

A last note is that the different repository mangers are surprisingly similar as to how they work and configured. It must be something to with where they all come from.

apt-cacher-ng

2008-07-28T13:08:00.003+02:00

I've been trying to get a decent apt-proxy going which doesn't force me to alter my sources.list file.
I tried apt-cacher, which is supposed to work, but it didn't for me.
Then I tried apt-cacher-ng.

(At my office we connect to the internet through a proxy server which requires username/password authentication,
so obviously I needed to configure apt-cacher-ng to connect
through our normal web proxy to be able to access the internet)

But it gave met the following error when I tried to use it:
407 Proxy Authentication Required

after struggling for some time, I figured out on this Russian site how to fix my problem:
http://linuxforum.ru/index.php?s=c9cb81224e4e338dc7ba84b6857dca5f&showtopic=69037&st=0&p=661582&#entry661582

It turns out the sample config file (/etc/apt-cacher-ng/acng.conf) is making you configure the proxy wrongly.
So in stead of configuring like:
proxy: http://user:pass@srv:port
do it like:
proxy: user:pass@srv:port

Now that I could configure my apt-cacher-ng to connect through and authenticate to our internet proxy, I'm able to switch to using it by merely editing /etc/apt/apt.conf:
Acquire::http { Proxy "http://myaptcacherng:3142"; };
//Acquire::http { Proxy "http://networkproxy:3142"; };

(lines starting with // are considered comments)

To Import .deb files from the local apt cache:
# let apt-cacher-ng use the .deb files that are already in /var/cache/apt/archives/
sudo mkdir -p /var/cache/apt-cacher-ng/_import
sudo chown apt-cacher-ng /var/cache/apt-cacher-ng/_import
sudo cp -al /var/cache/apt/archives/* /var/cache/apt-cacher-ng/_import/
# browse to and click "Start Import"
(from http://ubuntuforums.org/archive/index.php/t-981085.html )