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Verbose class loading

At work, a couple of long time experience Java devs were having build issues. They didn't know where their build system was pulling in a class from.
They didn't know that the JVM has a verbose class loading option.

If you run java -h, you will see this in the output:

    -verbose:[class|gc|jni]
                 enable verbose output

If you invoke your JVM like this:

java -verbose:class myHelloWorld

then the output will be very verbose as the class loader prints out detailed of all the classes loaded during startup and during the finding and running of your class.

e.g.

[Loaded java.net.URLConnection from /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rt.jar]
[Loaded sun.net.www.URLConnection from /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rt.jar]
[Loaded sun.net.www.protocol.file.FileURLConnection from /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rt.jar]
[Loaded sun.net.www.MessageHeader from /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rt.jar]
[Loaded java.io.FilePermission from /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rt.jar]



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