Sarat Dontula

Design patterns in jdk. Nice Post.

2011-02-10T14:39:00.000-08:00

http://www.briandupreez.net/2010/11/design-patterns-in-jdk.html

Maven

2010-02-04T09:35:00.000-08:00

UPDATE VERSION NUMBERS IN MULTI MODULE PROJECT:- mvn -e release:update-versions -DautoVersionSubmodules=true

View Super POM via effective-pom:- mvn help:effective-pom
Maven has:- Lifecycles, Phases, Plugins and Goals.

mvn deploy : deploy is a lifecycle. Which has phases verification, compilation, testing and packaging.

Executing phase or goal: mvn compile:compile jar:jar

Prepare your project to go offline: mvn dependency:go-offline

Go offline: mvn -o

Help for plugin:- mvn help:describe –D
Ex:- mvn help:describe -Dplugin=help -Dfull

Help for profiles:- mvn help:active-profiles

List hierarchy of dependencies:- mvn dependency:tree

List dependencies in alphabetic form:- mvn dependency:resolve

List plugin dependencies in alphabetic form:- mvn dependency:resolve-plugins

Analyze dependencies and list any that are unused, or undeclared.:- mvn dependency:analyze

Printing exception stack trace for a goal:- mvn -e

Output debugging info for a goal:- mvn -X

Debugging a unit test:- mvn test -Dmaven.surefire.debug

Manual Profile activation:- mvn –P YourProfile

Release using maven:- mvn release:perform

Creating archetype from project:- mvn archetype:create-from-project

wget with basic authentication.

2009-07-31T13:08:00.000-07:00

Here's how you download a file from internet which is secured by basic authentication. Replace myusername, mypassword with your own username and password.


wget http://download_file --http-user=myusername --http-passwd=mypassword

Hudson init script for Ubuntu 9.04

2009-07-29T18:13:00.000-07:00

Hudson init script for ubuntu 9.04. This is available on hudson's website too.

http://wiki.hudson-ci.org/display/HUDSON/Installation+and+Execution

This is what worked for me. The one hudson website is for linux. This you can use as is without modifications (except for "RUN_AS") on ubuntu


#!/bin/sh

DESC="Hudson CI Server "
NAME=hudson
PIDFILE=/var/run/$NAME.pid
RUN_AS=sysadm

d_start() {
 start-stop-daemon --start --quiet --background -m --pidfile $PIDFILE --chuid $RUN_AS --exec /usr/bin/java -- -Dhudson.scm.CVSSCM.skipChangeLog=true -jar /opt/hudson/hudson.war
}

d_stop() {
 start-stop-daemon --stop --quiet --pidfile $PIDFILE
 if [ -e $PIDFILE ]
  then rm $PIDFILE
 fi
}

case $1 in
 start)
 echo -n "Starting $DESC: $NAME "
 d_start
 echo "."
 ;;
 stop)
 echo -n "Stopping $DESC: $NAME "
 d_stop
 echo "."
 ;;
 restart)
 echo -n "Restarting $DESC: $NAME "
 d_stop
 sleep 1
 d_start
 echo "."
 ;;
 *)
 echo "usage: $NAME {start|stop|restart}"
 exit 1
 ;;
esac

exit 0

SSH without Password

2009-07-29T18:06:00.000-07:00

I got information from this site

http://www.csua.berkeley.edu/~ranga/notes/ssh_nopass.html

SSH Without a Password

The following steps can be used to ssh from one system to another without specifying a password.
Notes:

* The system from which the ssh session is started via the ssh command is the client.
* The system that the ssh session connects to is the server.
* These steps seem to work on systems running OpenSSH.
* The steps assume that a DSA key is being used. To use a RSA key substitute 'rsa' for 'dsa'.
* The steps assume that you are using a Bourne-like shell (sh, ksh or bash)
* Some of this information came from:
http://www.der-keiler.de/Mailing-Lists/securityfocus/Secure_Shell/2002-12/0083.html

Steps:

1.

On the client run the following commands:


$ mkdir -p $HOME/.ssh
$ chmod 0700 $HOME/.ssh
$ ssh-keygen -t dsa -f $HOME/.ssh/id_dsa -P ''

This should result in two files,


$HOME/.ssh/id_dsa (private key) and 
$HOME/.ssh/id_dsa.pub (public key).


Copy $HOME/.ssh/id_dsa.pub to the server.

3.

On the server run the following commands:


$ cat id_dsa.pub >> $HOME/.ssh/authorized_keys2
$ chmod 0600 $HOME/.ssh/authorized_keys2

Depending on the version of OpenSSH the following commands may also be required:


$ cat id_dsa.pub >> $HOME/.ssh/authorized_keys
$ chmod 0600 $HOME/.ssh/authorized_keys

An alternative is to create a link from authorized_keys2 to authorized_keys:


$ cd $HOME/.ssh && ln -s authorized_keys2 authorized_keys

4.

On the client test the results by ssh'ing to the server:


$ ssh -i $HOME/.ssh/id_dsa server

5.

(Optional) Add the following $HOME/.ssh/config on the client:


Host server
IdentityFile ~/.ssh/id_dsa

This allows ssh access to the server without having to specify the path to the id_dsa file as an argument to ssh each time.

HUDSON: THINGS TO REMEMBER [Skip Change Log]

2009-07-29T17:10:00.000-07:00

While starting hudson use:

java -Dhudson.scm.CVSSCM.skipChangeLog=true -jar hudson.war

This makes sure that hudson skips computing change log. Computing change log option is
slow for one thing and caused a lot of problems while I was setting it up in our projects.

Carnatic Music Website.

2009-07-11T12:17:00.000-07:00

http://www.ecse.rpi.edu/Homepages/shivkuma/personal/music/index.html

Professor Shiv Kumar Kalyanaraman's carnatic music archive. Wonderful website for carnatic music.

Move sqlserver tables to dbo user

2009-06-29T08:45:00.000-07:00

SELECT 'ALTER SCHEMA dbo TRANSFER ' + SCHEMA_NAME(schema_id) + '.' + name
FROM sys.tables
WHERE schema_id != SCHEMA_ID('dbo');

Starting JavaDB (Derby) in glassfish.

2009-06-21T22:18:00.000-07:00

I was following sahoo's Blog for creating an enterprise application with ejb3.0.
http://weblogs.java.net/blog/ss141213/archive/2005/12/using_java_pers.html

Ran into problem since JavaDB isn't started automatically when glassfish starts.

Error was "Error connecting to server localhost on port 1527 with message Connection refused: connect."

Solution:

You will have to issue below command to start derby database:

GlassFishHome/bin/> asadmin start-database

Hope this helps someone having similar issues.

Samba File Sharing Ubuntu

2009-06-20T11:44:00.000-07:00

SSH server is disabled by default in ubuntu. From package manager select & install ssh-server.

Samba File Sharing:

Setup up username & password:
smbpasswd -a
you'll be prompted to set the password.

Restart Samba service to take effect: [Just for good measure]
sudo /etc/init.d/samba restart

UBUNTU setting up environment variables.

2009-06-20T11:42:00.000-07:00

Use file /etc/bash.bashrc to setup new environment variables.

Do not use: /etc/profile
Do not use: /etc/environment file might work too.

Procedure:

1. Edit: /etc/bash.bashrc
2. Add this line to the end of the file. This sets JAVA_HOME

export JAVA_HOME=/usr/lib/j2sdk1.5-sun/

Linux helpful commands

2009-06-20T11:34:00.000-07:00

List of processes:
Solaris stats: prstat
Redhat stats: top

COMMON:
more /proc/version --- To see which version of linux
cat /proc/cpuinfo
cat /proc/meminfo

Creating symbolic link (shortcut in *unix) :
ln -s file_name shortcutname

Placing java in your path:
create link to the version of java into /usr/bin

Linux Runlevels:
who -r (gives run level of the system)
vi \etc\inittab (shows you the runlevel system is starting)

cd \etc\rc5.d (start up scripts for run level 5. K's represent donot start. S's represent start)
cd \etc\rc3.d (start up scripts for run level 5. K's represent donot start. S's represent start)
mv K36mysqld S36mysqld

ln -s ../init.d/jboss S36Jboss
mv S36Jboss K36Jboss
rm K36Jboss

WGET: [Connect to internet and download a file]

wget http://download_file_url

SQL to drop an index on table.

2009-06-20T11:29:00.000-07:00

SQLServer:
DROP INDEX address.ix_address_loc;

Syntax for Microsoft SQLJet (and Microsoft Access):
DROP INDEX index_name ON table_name

Syntax for IBM DB2 and Oracle:
DROP INDEX index_name

Syntax for MySQL:
ALTER TABLE table_name DROP INDEX index_name

SQL for alter column

2009-06-20T11:27:00.000-07:00

Sqlserver:

alter table customer alter column customer_name varchar(50);

Oracle Timestamp

2009-06-20T11:25:00.000-07:00

update customer set timestamp=to_date('1998/05/31:12:00:00AM', 'yyyy/mm/dd:hh:mi:ssam') where customer_id=48303

More Info:
http://infolab.stanford.edu/~ullman/fcdb/oracle/or-time.html

DB2 Timestamp

2009-06-20T11:23:00.000-07:00

SELECT STATEMENT:
select count(*) from customer where timestamp >='2010-01-01-00.00.00';

UPDATE (OR) INSERT STATEMENT:
update customer set timestamp=('2011-01-01-00.00.01.000000') where timestamp='2010-01-01-00.00.00';

Sql Server timestamp field

2009-06-20T11:19:00.000-07:00

INSERT (OR) UPDATE STATEMENTS:

insert into customer (customer_id,timestamp) values (17982698, '2005-10-17T00:00:00.0');

SELECT STATEMENTS:

select count(*) from customer where timestamp >= convert(datetime, '2006/10/01') and issue_date <=convert(datetime, '2007/09/30');

Sql Current Timestamp.

2009-06-20T11:16:00.000-07:00

For mysql, sqlserver, even db2 : current_timestamp

For oracle: sysdate

For mysql (one more function): now()

MySQL mysqldump tablename.MYD not found (Errcode: 24) when using LOCK TABLES

2009-06-20T11:11:00.000-07:00

In mysql 4.1 --opt option of mysqldump was made default.

This makes mysql to LOCK TABLES.

SOLUTION:
Use --skip-lock-tables to disable.

Creating MySql Database & Setting up users.

2009-06-20T11:06:00.000-07:00

Creating mysql Datbase:
1. At mysql command prompt issue command

create database <>;

2. Giving all users access to all the datbases from the server.

GRANT ALL PRIVILEGES ON *.* TO 'user'@'localhost' IDENTIFIED BY 'some_pass' WITH GRANT OPTION;

3. Giving all users access to all the datbases from remote machines. '%' in the query signifies that.

GRANT ALL PRIVILEGES ON *.* TO 'user'@'%' IDENTIFIED BY 'some_pass' WITH GRANT OPTION;

4. VERY VERY IMPORTANT DO NOT FORGET:
FLUSH PRIVILEGES;

LINUX MYSQL GOTCHAS

2009-06-20T10:56:00.000-07:00

1. bind-address : If your server's ip doesn't change. Might want to make it your server's ip address. Just makes it easier to troubleshoot connectivity issues.

2. Have to have this under mysqld [this disables mysql's case sensitivity. This is only a feature on *unix operating systems. Telling you it can be quite annoying...]
lower_case_table_names = 1

Other key parameters under [mysqld] which can be quite handy.

key_buffer = 128M
max_allowed_packet = 5GB
transaction_isolation = READ-UNCOMMITTED [Especially when working with some persistence middleware provider like ejb2.1 app servers.]

3. /etc/mysql/my.cnf - Location of configuration file

4. /etc/init.d/mysql start - Starts mysql
5. /etc/init.d/mysql stop - Stops mysql
6. /etc/init.d/mysql restart - Restarts mysql.

How to import and export mysql database?

2009-06-20T10:54:00.001-07:00

This assumes that mysql is in your classpath. Replace "dbname" in the below command with your own database name.

mysqldump -u root -p dbname > dump.sql (export)

mysql -u USER -p dbname < dump.sql (import)

Code Snippet posting in Blogger using Syntax Highlighting

2009-01-10T11:00:00.001-08:00

Finally able to get code posting in Blogger working.
This url helped me get there http://blog.gpowered.net/2007/07/howto-post-code.html


public class HelloWorld {
/**
* @Copyright Sarat Dontula :-)
*/
public static void main(String[] args)
{
System.out.println("Hello World");
}
}

What worked for me . In Blogger Layout -> Edit HTML -> After <head> tag place below code. Change the host name.


<link href='http://sdontula.googlepages.com/SyntaxHighlighter.css' rel='stylesheet' type='text/css'/>

Just before <body> place below code

 
<script language='javascript' src='http://sdontula.googlepages.com/shCore.js'/>
<script language='javascript' src='http://sdontula.blogspot.com/shBrushCSharp.js'/>
<script language='javascript' src='http://sdontula.blogspot.com/shBrushXml.js'/>
<script language='javascript' src='http://sdontula.blogspot.com/shBrushPython.js'/>
<script language='javascript' src='http://sdontula.blogspot.com/shBrushXml.js'/>
<script language='javascript' src='http://sdontula.blogspot.com/shBrushPhp.js'/>
<script language='javascript' src='http://sdontula.blogspot.com/shBrushJScript.js'/>
<script language='javascript' src='http://sdontula.googlepages.com/shBrushJava.js'/>

Again google should make it easy for developers to post code. This is just insane :-(

Blogger Code Styling & Display.

2009-01-10T10:17:00.000-08:00

Found below url to style code on blogger.

http://rias-techno-wizard.blogspot.com/2008/08/display-css-codes-and-scripts-in-unique.html

I tried using syntaxhightlighting from http://code.google.com/p/syntaxhighlighter/ using this blog post http://www.fromjavatoruby.com/2008/10/ruby-syntax-highlighting-in-blogger.html without much luck.

I tried to host the .js and .css scripts on google page creator. May be google page creator doesn't serve resources if it sees some other domain is requesting it. (Remote Hot Linking). Will have to find out some other way.

It is crazy that blogger doesn't provide something out of the box to display code snippets. Driving me nuts !!!!

Apache Redirection

2009-01-09T15:18:00.000-08:00

Uncomment below three lines in apache/conf/httpd.conf file:

LoadModule proxy_module modules/mod_proxy.so
LoadModule proxy_http_module modules/mod_proxy_http.so
LoadModule rewrite_module modules/mod_rewrite.so

Add below lines lines to httpd.conf:

RewriteEngine on
ProxyRequests Off

Order allow,deny
Allow from all

#Actual Redirection Code Starts
RewriteRule ^/customer-url$ customer-url/ [R]
ProxyPass /customer-url/ http://localhost:8080/customer-url/
ProxyPassReverse /customer-url/ http://localhost:8080/customer-url/

Above we are making apache accept requests on port 80 for a server which is serving web pages on 8080. It mean http://localhost/customer-url gets it's pages from http://localhost:8080/customer-url .

How to test if a machine has access to the smtp server

2009-01-09T09:20:00.000-08:00

This url: http://support.microsoft.com/kb/304897
helps us in testing if server
is allowed to relay etc..

Basically you do:
1. telnet servername port
2. EHLO
3. RSET

(YOU SHOULD SEE MESSAGE AS A RESULT:
250 2.0.0 Resetting)

4. MAIL FROM:UserName@DomainName.com
(use an email belonging to the domain)

5. RCPT TO:RecipientName@DomainName.com
(use email belonging to the domain)

6. QUIT (TO EXIT)

Above should send out an email without errors.
This should tell us if we can configure email
properly.

Installing JBoss as service on Ubuntu

2008-12-18T12:53:00.000-08:00

Installing JBoss as service on Ubuntu

http://chiralsoftware.com/linux-system-administration/jboss-server-deployment.seam

Problem fix in fop 0.20. Hard return not recognized.

2008-12-12T08:16:00.000-08:00

Several days ago we had an issue with fop pdf generator. Fop wasn't recognizing hard returns in user comments and putting all of them in one big giant paragraph. It was an annoying problem.

In fop-0.93 there is an easy way to fix this problem:
<fo:block treatment="preserve">

For people who are stuck with fop 0.2 like we are have to use below workaround:

I'm using "splitstring" template to parse value from node "Comments" with pattern "hard return" which is represented by &xD . The strings generated by splitting are displayed in their own fo:block, thus preserving hard returns.

Below is the code.

I found split string function here:
http://www.exslt.org/str/functions/split/str.split.template.xsl.html

Code for the same is as below:

<xsl:call-template name="splitstring">
<xsl:with-param name="string">
<xsl:value-of select="Comments">
</xsl:value-of>
<xsl:with-param name="pattern">
<xsl:value-of select="''">
</xsl:value-of>
</xsl:with-param>
<xsl:template name="splitstring">
<xsl:param name="string"/>
<xsl:param name="pattern"/>
<xsl:choose>
<xsl:when test="not($string)" />
<xsl:when test="not($pattern)">
<xsl:call-template name="split-characters">
<xsl:with-param name="string"
select="$string" />
</xsl:call-template>
</xsl:when>
<xsl:otherwise>
<xsl:call-template name="split-pattern">
<xsl:with-param name="string"
select="$string" />
<xsl:with-param name="pattern"
select="$pattern" />
</xsl:call-template>
</xsl:otherwise>
</xsl:choose>
</xsl:template>

<xsl:template name="split-characters">
<xsl:param name="string" />
<xsl:if test="$string">
<fo:block>
<xsl:value-of select="substring($string, 1, 1)" />
</fo:block>
<xsl:call-template name="split-characters">
<xsl:with-param name="string"
select="substring($string, 2)" />
</xsl:call-template>
</xsl:if>
</xsl:template>

<xsl:template name="split-pattern">
<xsl:param name="string" />
<xsl:param name="pattern" />
<xsl:choose>
<xsl:when test="contains($string, $pattern)">
<xsl:if test="not(starts-with($string, $pattern))">
<fo:block>
<xsl:value-of select="substring-before($string, $pattern)" />
</fo:block>
</xsl:if>
<xsl:call-template name="split-pattern">
<xsl:with-param name="string"
select="substring-after($string, $pattern)" />
<xsl:with-param name="pattern"
select="$pattern" />
</xsl:call-template>
</xsl:when>
<xsl:otherwise>
<fo:block>
<xsl:value-of select="$string" />
</fo:block>
</xsl:otherwise>
</xsl:choose>
</xsl:template>

My Little one

2008-12-08T10:38:00.000-08:00

My little one "Srikar Dontula" 's picture on my new T-mobile blackberry pearl 8100. Blackberry was initially a pain to use. Getting used to it a little bit now. Love it so far....

My first piano recital

2008-12-08T10:31:00.001-08:00

Picture from my first piano recital (12/06/08). I have been taking classes since end of August '08. Recitals will be every 6 months. Will have to see if I can post a video next time around.

Next to me is my teacher Brenda Meether. I take classes at her piano studio. Her web location: http://www.brendameethermusic.com/

SCP transferring files.

2008-12-08T08:58:00.000-08:00

Command to upload files to a server:

scp <file-name> user@server-ip <destination-file-name>

ex: scp mail.jar sarat@some-ip mail.jar

[Above puts the file in user's home directory. Specify particular directory if you wish you place file in a different location]

Command to downloading files from a server:

scp user@server-ip:<file-name> <local-directory-location>

ex: scp sarat@some-ip:mail.jar /home/sarat/Desktop/

Using cadaver for querying webdav

2008-12-04T10:30:00.000-08:00

Home page for cadaver: http://www.webdav.org/cadaver/

On ubuntu you can install it from repositories. Below are steps to do the same.
Steps on how to install cadaver from ubuntu repositories.
(i) From System -> Administration -> Synaptic Package Manager -> Type "Cadaver" and hit search.
(ii) Click on checkbox right next to cadaver -> Select mark for installation -> Hit Apply.

Using cadaver: (I looked for documentation on home page and didn't find any. Below steps might help you get started)
1. type in "cadaver" on the command line.
2. open http://< ip-address >/
3. cd ../exchange/some-folder/calendar/ (asked me for credentials)
4. ls - to list files. (was able to list files on webdav)
5. propget file-name.EML (lists propeties)
5. get file-name.EML (gets webpage. shows it on the terminal)
6. propnames test203-1.EML
7. help (to get more help)
8. help command (to list help information) ex:- help ls

Ubuntu x-windows problem fix.

2008-12-04T10:15:00.000-08:00

Recently one of our desktop after restart distorted the whole screen.

Tried below steps to solve the problem.

1. Reinstall ubuntu-desktop (didn't work)
sudo apt-get remove ubuntu-desktop (removed ubuntu desktop)
sudo apt-get install ubuntu-desktop (re-installed it)

2. sudo dpkg --configure -a (didn't work)

3. sudo dpkg-reconfigure xserver-xorg (this solved the problem)
After issuing the command went through all configuration screens, selected defaults and rebooted ubuntu to see the login screens undistorted.

Note:
1. From login screen to go to command line use "Ctrl + Alt + F1"
2. To go back to login screen use "Ctrl + Alt + F7"
Looks like ubuntu has 6 tty sessions. F7 takes you to x-windows.

Ubuntu upgrade broke network manager.

2008-12-04T10:07:00.000-08:00

My amd 64 network manager broke after today's upgrade. Followed below link to solve the problem

https://bugs.launchpad.net/bugs/279433

Steps:
1. Downloaded: network-manager_0.7~~svn20080928t225540+eni0-0ubuntu2_amd64.deb

from link: https://launchpad.net/ubuntu/intrepid/amd64/network-manager/0.7~~svn20080928t225540+eni0-0ubuntu2

2. Moved existing network-manager deb from /var/cache/apt/archives/ to the desktop

mv /var/cache/apt/archives/network-manager-pptp_0.7~~svn20081015t024626-0ubuntu1.8.10.1_amd64.deb ~/Desktop

3. Copied "network-manager_0.7~~svn20080928t225540+eni0-0ubuntu2_amd64.deb" to /var/cache/apt/archives folder.

4. Restarted the box. Networking started working!!

Open source LDAP browser/editor

2008-12-03T23:11:00.001-08:00

LDAP BROWSER/EDITOR: http://www-unix.mcs.anl.gov/~gawor/ldap/download.html

JBoss Notes

2008-12-03T23:03:00.000-08:00

1. How to install jboss as service in ubuntu:
Create link in /etc/init.d/jboss to /usr/local/jboss/bin/jboss_init_redhat.sh using below command:
ln -s /etc/init.d/jboss /usr/local/jboss/bin/jboss_init_redhat.sh

2. How to bind JBoss to a particular IP address rather than localhost.
(You might be required to do this to call session beans using RMI)
JBOSS Bind Address JAVA_OPTS:
set JAVA_OPTS=%JAVA_OPTS% -Dbind.address=10.10.50.20
link: http://blogs.adobe.com/livecycle/2008/03/livecycle_sample_jboss_runbat.html

3. How to restore JBoss persistence connection rather than restarting:
Under jmx-console for JBoss. Click on below link under "JCA"
name=jdbc/< your database jndi name >,service=ManagedConnectionPool
Click on flush cache button to restore connection to database.

4. Start & Stop JBOSS on solaris
svcadm enable network/jboss:default
svcadm disable network/jboss:default

svcs -l jboss
svcs -p jboss

5. Installing 2nd instance of JBoss.
Description: * default/deploy/jbossweb-tomcat55.sar/server.xml:

o change 8080 to 18080

* default/conf/jboss-service.xml

o change 8083 to 18083
o change 1099 to 11099
o change 1098 to 11098
o change 4445 to 14445
o change 4444 to 14444

* default/conf/jboss-minimal.xml

o change 1099 to 11099
o change 1098 to 11098

* default/deploy/jms/uil2-service.xml

o change 8093 to 18093

Starting hsqldb database

2008-12-03T22:56:00.000-08:00

java -classpath lib/hsqldb.jar org.hsqldb.Server

Glassfish Notes

2008-12-03T22:35:00.001-08:00

Starting and Stopping a Domain:
./asadmin start-domain < domain-name >

Setting up SQL Server Datasource in glassfish:
jtds class: net.sourceforge.jtds.jdbcx.JtdsDataSource
resource type: javax.sql.ConnectionPoolDataSource

Disabling foreign keys for all tables in a database.

2008-12-03T22:27:00.000-08:00

DROP ALL FOREIGN KEYS SQLSERVER:
SELECT
'
' +
CASE WHEN xtype = 'TR' THEN
'Drop Trigger ' + [Name]
ELSE
'ALTER TABLE ' + object_name(parent_obj) + ' DROP FOREIGN KEY ' + [name]
END +
';'
AS Script
from sysobjects where xtype IN ('F','TR')

DISABLE FOREIGN KEYS SQL Server:
EXEC sp_MSforeachtable @command1="ALTER TABLE ? NOCHECK CONSTRAINT ALL"
EXEC sp_MSforeachtable @command1="ALTER TABLE ? DISABLE TRIGGER ALL"

RE-ENABLING FOREIGN KEYS:
EXEC sp_MSforeachtable @command1="ALTER TABLE ? CHECK CONSTRAINT ALL"
EXEC sp_MSforeachtable @command1="ALTER TABLE ? ENABLE TRIGGER ALL"

IN MYSQL:
Just add "sessionVariables=FOREIGN_KEY_CHECKS=0" to your JDBC URL.

Session expired error while deploying icefaces application on TOMCAT.

2008-12-03T22:22:00.000-08:00

Session expired errors.
Fix by editing tomcathome/conf/context.xml

Look for below comment in context.xml
Uncomment this to disable session persistence across Tomcat restarts

Uncomment below configuration item
<Manager pathname="" />

AS400 Cheat Sheet.

2008-12-03T22:15:00.000-08:00

1. How to view version of AS400:
1. GO LICPGM -> 10 -> F11
2. DSPSFWRSC (display software resources Hit F11 to see version)

2. How to create a new database on AS400 using any sql tool
create collection databasename (new schema command)

3. Clear contens of a file
clrpfm library/filename (clear contents of a file)

4. Get IP address of as400
On the iSeries you can use CFGTCP option 10.

5. View ports being used
NETSTAT from PC or AS400.

6. Kill a program immediately (in QShell) like [kill -9 in unix]
On as400 it is: kill -12

7. ALTER BLOB LENGTH
alter table attachment alter column document set data type blob(10485760)

8. DSPFFD (DISPLAY FULL FILE DESCRIPTION)
DISPLAYS COLUMN LENGTHS AND OTHER INFORMATION ABOUT A FILE.

9. Start QShell on AS400
Command: strqsh

Ubuntu Service Management

2008-12-02T14:21:00.000-08:00

To disable a startup service use: sudo update-rc.d -f mysql remove
(had to use -f option to force remove)
To make mysql startup when ubuntu boots: sudo update-rc.d mysql defaults

sudo update-rc.d mysql remove
update-rc.d: /etc/init.d/mysql exists during rc.d purge (use -f to force)

sudo update-rc.d -f mysql remove
Removing any system startup links for /etc/init.d/mysql ...
/etc/rc0.d/K21mysql
/etc/rc1.d/K21mysql
/etc/rc2.d/S19mysql
/etc/rc3.d/S19mysql
/etc/rc4.d/S19mysql
/etc/rc5.d/S19mysql
/etc/rc6.d/K21mysql

sudo update-rc.d mysql defaults
Adding system startup for /etc/init.d/mysql ...
/etc/rc0.d/K20mysql -> ../init.d/mysql
/etc/rc1.d/K20mysql -> ../init.d/mysql
/etc/rc6.d/K20mysql -> ../init.d/mysql
/etc/rc2.d/S20mysql -> ../init.d/mysql
/etc/rc3.d/S20mysql -> ../init.d/mysql
/etc/rc4.d/S20mysql -> ../init.d/mysql
/etc/rc5.d/S20mysql -> ../init.d/mysql

This is the link I followed: http://nixcraft.com/shell-scripting/542-ubuntu-linux-control-startup-services-scripts.html

SQL Server Problem Fixes

2008-12-02T11:06:00.000-08:00

***************
1. Apostrophe issue in sql statement:

select * from business where name = 'Craig's List';

Above statement fails.

Use Below: Have to replace single apostrophe with two apostrophes.

select * from business where name = 'Craig''s List';

***************

***************
2. Sql statement errors out when there are spaces in column names.

"contact on contractor" is column in contractorconversion table.
"BUSINESS NAME" is another column in contractorconversion table.

To get around use: \"<>\" around the column name.

String sqlStmt = "select cc.\"contact on contractor\" as contact from contractorconversion cc, business b where b.name=cc.\"BUSINESS NAME\" and cc.\"BUSINESS NAME\"=";
***************

Web Ajax Frameworks

2008-11-23T16:31:00.000-08:00

Consider ICEFACES, WICKET, STRIPES, zk.

http://stripesframework.org
http://icefaces.org
http://wicket.apache.org
http://zkoss.org

Important Links

2008-10-13T09:53:00.000-07:00

EJB:

http://www.theserverside.com/tt/articles/article.tss?l=NewFeaturesinEJB31-Part5

WEB SERVICES:
http://www.keith-chapman.org/2008/10/apache-axis2-tips-and-tricks.html

STRUTS2:
http://struts.apache.org/2.0.11.2/docs/struts-2-spring-2-jpa-ajax.html