FULL PRODUCT VERSION :
java version "1.5.0_05"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_05-b05)
Java HotSpot(TM) 64-Bit Server VM (build 1.5.0_05-b05, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux dev17.pub.qa.atl.jboss.com 2.6.9-22.0.1.ELsmp #1 SMP Tue Oct 18 18:39:02 EDT 2005 x86_64 x86_64 x86_64 GNU/Linux


A DESCRIPTION OF THE PROBLEM :
When starting an out-of-the-box JBoss 4.0.2/4.0.3SP1 we get random OutOfMemoryError Error very early on startup, about 30% of the time.

This is not really due to JBoss code, we have a minimal testcase that can be used to reproduce the problem.

This happens only on the 64bit version of jdk5 on Linux. It works fine on older jdk versions, or the 32 bit versions. It works fine also using the 64bit JRockit on Linux.

The issue was discussed here: http://www.jboss.com/index.html?module=bb&op=viewtopic&t=74994&postdays=0&postorder=asc&start=0

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
  To run the testcase use:

java TestOOM jboss-4.0.2/server/all/lib/ test.xml

Basically point it to a directory with a lot of jar files (e.g. the server/all/lib directory of jboss that contains 45 jars) plus any non-jar, non-empty file (e.g. test.xml)

In this example we use those paths to contract a URL[] passed to a URLClassLoader, then try to load a non-existing class. Most of the times this tests will produce an OOM Error, at the point when the non-jar file is openned

ACTUAL -
java TestOOM jboss-4.0.2/server/all/lib/ test.xml
#0 file:/home/dimitris/jboss-4.0.2/server/all/lib/activation.jar
#1 file:/home/dimitris/jboss-4.0.2/server/all/lib/autonumber-plugin.jar
#2 file:/home/dimitris/jboss-4.0.2/server/all/lib/avalon-framework.jar
#3 file:/home/dimitris/jboss-4.0.2/server/all/lib/bcel.jar
#4 file:/home/dimitris/jboss-4.0.2/server/all/lib/bindingservice-plugin.jar
#5 file:/home/dimitris/jboss-4.0.2/server/all/lib/bsh-1.3.0.jar
#6 file:/home/dimitris/jboss-4.0.2/server/all/lib/bsh-deployer.jar
#7 file:/home/dimitris/jboss-4.0.2/server/all/lib/commons-httpclient.jar
#8 file:/home/dimitris/jboss-4.0.2/server/all/lib/commons-logging.jar
#9 file:/home/dimitris/jboss-4.0.2/server/all/lib/hsqldb-plugin.jar
#10 file:/home/dimitris/jboss-4.0.2/server/all/lib/hsqldb.jar
#11 file:/home/dimitris/jboss-4.0.2/server/all/lib/jacorb.jar
#12 file:/home/dimitris/jboss-4.0.2/server/all/lib/javax.servlet.jar
#13 file:/home/dimitris/jboss-4.0.2/server/all/lib/javax.servlet.jsp.jar
#14 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-cache.jar
#15 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-common-jdbc-wrapper.jar
#16 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-iiop.jar
#17 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-j2ee.jar
#18 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-jaxrpc.jar
#19 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-jca.jar
#20 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-jsr77.jar
#21 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-management.jar
#22 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-monitoring.jar
#23 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-remoting.jar
#24 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-saaj.jar
#25 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss-transaction.jar
#26 file:/home/dimitris/jboss-4.0.2/server/all/lib/jboss.jar
#27 file:/home/dimitris/jboss-4.0.2/server/all/lib/jbossha.jar
#28 file:/home/dimitris/jboss-4.0.2/server/all/lib/jbossmq.jar
#29 file:/home/dimitris/jboss-4.0.2/server/all/lib/jbosssx.jar
#30 file:/home/dimitris/jboss-4.0.2/server/all/lib/jgroups.jar
#31 file:/home/dimitris/jboss-4.0.2/server/all/lib/jmx-adaptor-plugin.jar
#32 file:/home/dimitris/jboss-4.0.2/server/all/lib/jnpserver.jar
#33 file:/home/dimitris/jboss-4.0.2/server/all/lib/jpl-pattern.jar
#34 file:/home/dimitris/jboss-4.0.2/server/all/lib/jpl-util.jar
#35 file:/home/dimitris/jboss-4.0.2/server/all/lib/license.html
#36 file:/home/dimitris/jboss-4.0.2/server/all/lib/log4j.jar
#37 file:/home/dimitris/jboss-4.0.2/server/all/lib/mail-plugin.jar
#38 file:/home/dimitris/jboss-4.0.2/server/all/lib/mail.jar
#39 file:/home/dimitris/jboss-4.0.2/server/all/lib/properties-plugin.jar
#40 file:/home/dimitris/jboss-4.0.2/server/all/lib/scheduler-plugin-example.jar
#41 file:/home/dimitris/jboss-4.0.2/server/all/lib/scheduler-plugin.jar
#42 file:/home/dimitris/jboss-4.0.2/server/all/lib/scout.jar
#43 file:/home/dimitris/jboss-4.0.2/server/all/lib/snmp-support.jar
#44 file:/home/dimitris/jboss-4.0.2/server/all/lib/webcallbackhandler.jar
#45 file:/home/dimitris/test.xml
java.lang.OutOfMemoryError
        at java.util.zip.ZipFile.open(Native Method)
        at java.util.zip.ZipFile.<init>(ZipFile.java:203)
        at java.util.jar.JarFile.<init>(JarFile.java:132)
        at java.util.jar.JarFile.<init>(JarFile.java:70)
        at sun.misc.URLClassPath$JarLoader.getJarFile(URLClassPath.java:579)
        at sun.misc.URLClassPath$JarLoader.<init>(URLClassPath.java:546)
        at sun.misc.URLClassPath$3.run(URLClassPath.java:324)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.misc.URLClassPath.getLoader(URLClassPath.java:313)
        at sun.misc.URLClassPath.getLoader(URLClassPath.java:290)
        at sun.misc.URLClassPath.findResource(URLClassPath.java:141)
        at java.net.URLClassLoader$2.run(URLClassLoader.java:362)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findResource(URLClassLoader.java:359)
        at TestOOM.main(TestOOM.java:49)


ERROR MESSAGES/STACK TRACES THAT OCCUR :
java.lang.OutOfMemoryError
        at java.util.zip.ZipFile.open(Native Method)
        at java.util.zip.ZipFile.<init>(ZipFile.java:203)
        at java.util.jar.JarFile.<init>(JarFile.java:132)
        at java.util.jar.JarFile.<init>(JarFile.java:70)
        at sun.misc.URLClassPath$JarLoader.getJarFile(URLClassPath.java:579)
        at sun.misc.URLClassPath$JarLoader.<init>(URLClassPath.java:546)
        at sun.misc.URLClassPath$3.run(URLClassPath.java:324)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.misc.URLClassPath.getLoader(URLClassPath.java:313)
        at sun.misc.URLClassPath.getLoader(URLClassPath.java:290)
        at sun.misc.URLClassPath.findResource(URLClassPath.java:141)
        at java.net.URLClassLoader$2.run(URLClassLoader.java:362)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findResource(URLClassLoader.java:359)
        at TestOOM.main(TestOOM.java:49)


REPRODUCIBILITY :
This bug can be reproduced often.

---------- BEGIN SOURCE ----------
import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Properties;

public class TestOOM
{
   public static void main(String[] args)
   {
      ArrayList urls = new ArrayList();
      try
      {
         for (int i = 0; i < args.length; i++)
         {
            File file = new File(args[i]);
            if (file.isDirectory())
            {
               File[] files = file.listFiles();
               for (int j = 0; j < files.length; j++)
               {
                  urls.add(files[j].toURL());
               }
            }
            else
            {
               urls.add(file.toURL());
            }
         }
      }
      catch (MalformedURLException ignore)
      {
      }

      URL[] cp = (URL[])urls.toArray(new URL[urls.size()]);
      for (int i = 0; i < cp.length; i++)
      {
         System.out.println("#" + i + " " + cp[i]);
      }


      URLClassLoader ucl = new URLClassLoader(cp);
      try
      {
         ucl.findResource("foo.bar.Class");
      }
      catch (Throwable t)
      {
         // got it!
         t.printStackTrace();
         System.exit(1);
      }
   }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
There is not really workaround for this, other than avoiding open non zip files with ZipFile, but this not always under our control.

This is a really annoying bug.