JBoss AS and internal libraries

Last week, I discovered something nice on the JBoss application server.
Imagine you have a webapplication (deployment : EAR) which has the following dependency:

<dependency>
    <groupId>commons-httpclient</groupId>
    <artifactId>commons-httpclient</artifactId>
    <version>3.0.1</version>
</dependency> 

Now, you can put the library on provided:

<dependency>
    <groupId>commons-httpclient</groupId>
    <artifactId>commons-httpclient</artifactId>
    <version>3.0.1</version>
    <scope>provided</scope>
</dependency> 

... but be aware that the implementation version of commons-httpclient is the same in JBoss as you specified in your pom.xml. There are 2 ways to check this:

• browse to $JBOSS_HOME/lib and open commons-httpclient.jar. Go to: META-INF/MANIFEST.MF. You will see this:
  Manifest-Version: 1.0
  Specification-Title: JBoss
  Created-By: ari-49095-20050826-1856-linux-ia32 (BEA Systems, Inc.)
  Ant-Version: Apache Ant 1.6.5
  Implementation-Title: JBoss [Trinity]
  Specification-Version: 1.0
  Specification-Vendor: Apache Software Foundation
  Implementation-Vendor-Id: http://www.jboss.org/
  Extension-Name: httpclient
  Implementation-Version: 3.0.1
  Implementation-Vendor: Apache Software Foundation
  Implementation-URL: http://www.jboss.org/
  ... which means, the implemenation version is 3.0.1.
• ... but last week, I discovered the $JBOSS_HOME/jar-versions.xml file which contains ALL the implementation versions. But it's confusing to look at this file:
  

  ...
  <?xml version="1.0" encoding="UTF-8"?>
  <jar-versions>
    <jar name="FastInfoset.jar" specVersion="1.0" specVendor="JBoss (<a href="http://www.jboss.org/">http://www.jboss.org/</a>)" specTitle="ITU-T Rec. X.891 | ISO/IEC 24824-1 (Fast Infoset)" implVersion="1.2.2" implVendor="Sun Microsystems, Inc." implTitle="Fast Infoset Implementation " implVendorID="com.sun" implURL="<a href="http://www.jboss.org/&quot">http://www.jboss.org/&quot</a>; sealed="false" md5Digest="c16cec395b7e7ed1f18e8ec58a5992d7"/>
    <jar name="activation.jar" specVersion="1.1" specVendor="Sun Microsystems, Inc." specTitle="JavaBeans(TM) Activation Framework Specification" implVersion="1.1" implVendor="Sun Microsystems, Inc." implTitle="Sun Java System Application Server" implVendorID="com.sun" implURL="<a href="http://www.jboss.org/&quot">http://www.jboss.org/&quot</a>; sealed="false" md5Digest="f7209f1d5a729bd3ec5b9a8f64aaf52d"/>
  ...

  
  So I wrote a small XSL file for mark up.
  1. create the file jar-versions.xsl next to jar-versions.xml with the following content:
     

      <?xml version="1.0"?>
      <!-- @author Jochen Hebbrecht (RealDolmen) -->
     <xsl:stylesheet xmlns:xsl="<a href="http://www.w3.org/TR/WD-xsl">&#10">http://www.w3.org/TR/WD-xsl">&#10</a>;	<xsl:template match="/">
     			<h1>JBoss internal libraries</h1>
     			<table width="100%" border="1">
     				<xsl:for-each select="//jar">
     					<tr>
     						<td><xsl:value-of select="@name"/></td>
     						<td><xsl:value-of select="@implVersion"/></td>
     					</tr>
     				</xsl:for-each>
     			</table>
     	</xsl:template>
     </xsl:stylesheet>

  2. add this line to jar-versions.xml
     

     <?xml version="1.0" encoding="UTF-8"?>
     <?xml-stylesheet type="text/xsl" href="jar-versions.xsl"?>
     ...

  3. just open the XML file and enjoy the layout ;-)!