Change Default Page of Tomcat

In Tomcat 5.5 you have to add the following line INSIDE your HOST element in ther server.xml

<Context path="" docBase="myApp" debug="0"/>

This is better than copying your application in the ROOT directory.
When googling around for this problem I also found the following solution (which works, but is real stupid):
The default Application, which is situated in the ROOT directory is precompiled so they recommended to uncomment the following in .../ROOT/WEB-INF/web.xml:

<!--
<servlet>
<servlet-name>org.apache.jsp.index_jsp</servlet-name>
<servlet-class>org.apache.jsp.index_jsp</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>org.apache.jsp.index_jsp</servlet-name>
<url-pattern>/index.jsp</url-pattern>
</servlet-mapping>
-->


to remove the precompilation. When you now edit the index.jsp it takes effect. So you only have to add a redirect in the index.jsp and voila :-)

Install JadClipse

You need it seldom, but it's nice to have one: a Decompiler.
JadClipse is a plugin for eclipse to implement jad into the Eclipse-IDE
First you need to downlod jad (1.5.8g) and JadClipse (i took JadClipse 3.2.4 for Eclipse 3.2).
Extract the downloaded jad*.zip to your preffered location.
Copy the downloaded net.sf.jadclipse_3.2.4.jar to your eclipse plugins directory and restart Eclipse with the -clean parameter (on windows: eclipse.exe -clean).
Go to Windows --> Preferences --> Java --> JadClipse and check the "Path to decompiler" that it points to the Jad-Executable (on windows: jad.exe)
Next check the File Association of *.class files under Windows --> Preferences --> General --> File Associations that they point to JadClipse.
Have Phun :-)

Automated FTP-Put in Shell-Script

If you want to make an automated FTP-Put just use the next few lines in your Shell-Script.

#!/bin/sh
echo -e "open ftp.example.com\nuser ftpuser ftppasswd\nbin\ncd toDirectory\nput file.example" |ftp -n

SvnAnt Recipe

When you want to use SvnAnt, you have to put svnant.jar, svnClientAdapter.jar and svnjavahl.jar (if you have not explicitly set javahl="false" in your svn-call) in your ANT_HOME directory.
Next is to announce the usage of svn in your Ant-File:

<taskdef resource="svntask.properties">

But this all doesn't work, if you haven't put your subversion bin directory to your PATH Variable.
When you have forgotten this you get the error-Message:
"Cannot use javahl nor command line svn client"

Usage of the svn task is then for example:

<svn username="user" password="secret" javahl="false">
<checkout url="https://checkout.com" destpath="//destPath"/>
</checkout>

Subversion & Ant

Today I experienced a little Problem with Subversion and my own Ant build.xml.
Subclipse added my WEB-INF/classes directory to the repository and my build.xml deleted this directory before building it new. Therefore also the .svn directory was deleted and I always got the error message:
Working copy not locked; this is probably a bug, please report
When googling around I found some newsgroup entries, saying I shall retrieve my old .svn directory
...
...
...
Very funny.
The only way to restore my workspace was to synchronize my latest changes step by step, then delete the whole Project in workspace, remove the class directory DIRECTLY from the SVN-Repository and checkout the Project again.

Java Property-Files

Things I learned for today:

• When using a .property file, be careful to use exactly the same key than in code.
  
• When using a .property file, don't forget to remove quotes from your copied String.
  

Java Obfuscator

... don't know if I need an Obfuscator sometimes, but here is a Link for all possible open-source and commercial Ofcuscators ...

Network Problems with Eclipse Software-Updater

After a successful installation of some plugins in Eclipse 3.2 I tried to install some additional Plugins. After "Help --> Software Updates --> Find and Install --> Search for new features to install" and pressing "Finish" after selecting a Plugin Site i got the following Error Message:
"Network connection problems encountered during search"
when I switched to Detail-View I got: "Unable to access http://..."

Neither restarting Eclipse nor restarting my computer had any effects on this error.
When I selected: "Windows --> Preferences --> Install / Update" and did ANY change there, the Update Process was working again.
My decision: Eclipse stores the selected mirror anywhere in the .metadata and does this WRONG. After applying any change in the Install/Update properties, the mirror-link is lost and the installer works again

Eclipse Startup-Parameter

eclipse.exe -clean -vmargs -Xms240m -Xmx240m
-clean --> Enables clean registration of plug-in (some plug-ins do not always register themselves properly after a restart)

-vmargs --> Allows you to pass in standard VM arguments

• Xms --> Minimum VM-Memory
• Xmx --> Maximum VM-Memory
  

OutOfMemoryException with large Ant JUnit TestSuite

With large TestSuites Ant sometimes runs out of memory.
You can prevent this by increasing the Ant Memory. Simply type:
"export ANT_OPTS=-Xmx512M" on your console

Blackdown Java vs. Sun Java

Found an interesting "bug" (it isn't a real bug, but choose yourself): If you have a Date (no matter if java.sql.Date or java.util.Date) in Daylight-saving Time before 1981 Blackdown chooses the historical way (no Daylight saving Time between 1948 and 1980) and Sun does ignore this historical point.
This isn't a real problem until you mix up the two distributions (eg. client-server application)

Problems with keep-together.within-page="always" for preventing Page-Breaks

I know this Blog has more to do with xsl:fo than with Java but I had another Problem with my Stylesheet.
I wanted to add keep-together.within-column="always" to a <fo:table> tag but it did'nt keep the block together. So I googled and found out , that you have to add
keep-with-next="always" to your <fo:table-row> tag
For example :
<fo:table-row keep-with-next="always">

db2 - SQL Tutorial

In search for a "group-by" howto I found a nice german
db2 - SQL-Tutorial

Edited 07.03.07:new Link db2 SQL Tutorial

Eclipse Shortcuts

I don't know, what a single PDF has lost on sourceforge, but it is real great!
http://eclipse-tools.sourceforge.net/shortcuts.html

Page XX of XX with xsl-fo

If you want the Page-number in a XSL you use <fo:page-number>
but what if you want the pagenumber followed by the total pagenumber ?
the trick is to add <fo:page-number-citation ref-id="endofdoc"/> with the tag
<fo:block id="endofdoc"/> at the end of the stylesheet.

Prevent Pagebreak with xsl-fo

If you want to prevent Pagebreak within a fo:table-row you have to add the following attribute to your row:
<fo:table-row column="always">
Other possible values than "always" are:

• auto ... no restrictions for page break
• Integer-Values ... e.g. 3. No Pagebreak if there is no other, stronger pagebreak requirement

keep-together. can also be used with

• within-column for pagebreak in one line
  
• within-page for pagebreak in one page

the Attribute can be added to

• fo:basic-link
• fo:block
• fo:block-container
• fo:inline
• fo:inline-container
• fo:list-block
• fo:list-item
• fo:list-item-body
• fo:list-item-label
• fo:table
• fo:table-and-caption
• fo:table-caption
• fo:table-row
  

How to concatenate PDFs without pain

Found a real interesting Article of concatenating PDFs
How to concatenate PDFs without pain

Welcome

In this Blog I want to post Tips & Tricks for Java Developers which I consider as beeing important or assistant.