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Check if the jar file is loaded?

I have a custom jar file in tomcat lib / folder. From my knowledge, any jar file in this folder will be loaded on startup.

Is there anyway I can check if a specific jar file is loaded or not?

I am running tomcat-6.0.35.A on unix rhel5.

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I think I've seen which jars are opened at startup in one of the Tomcat log files. If it weren't for me, I could think of two possible alternatives:



  1. Add -verbose:class

    in JAVA_OPTS

    Tomcat startup scripts. It should print the classes as they are loaded by the JVM (a lot of output). Grep log file (or standard stdout

    ) to find if classes are listed from your jar
  2. Use the Linux lsof command to view the files opened by the Tomcat process.
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The boxes are not actually loaded at startup. But Tomcat classloader loads classes from these jars. You can check if any class is available from the jar:

  • trying to load this class from your code eg. getClass().getClassloader().loadClass(className)

  • trying to load a class as a resource like getClass().getResource("/" + className.replace('.', '/') + ".class")



In the second case, you must have the name or your jar file in the url returned getResource()

.

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