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I am trying to list the order in which the Java class loader is loading my classes. if I use -verbose parameter it will list every single interface/class it loads, including tons of interfaces such as Serializable, exceptions etc. Is there a way to tweak this output so it only shows which classes are loaded in the class my main method is defined?

Alexander Oh
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Bober02
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2 Answers2

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I guess your best bet is to do the following:

  • Output some fixed text once your main method starts and right before it ends.
  • Pipe the verbose output into a file
  • Use things like less or grep to find the classes loaded between the two tags from the main method.

There's a similar question and some answers here: Is there a way to get which classes a ClassLoader has loaded?

Did you try -verbose:class?

Community
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nwinkler
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    In case anyone is wondering where this is documented: https://docs.oracle.com/en/java/javase/11/tools/java.html – Renato Jul 01 '21 at 13:30
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Here's a sed expression that will parse the output of java -verbose:class to produce pairs of loaded class name and its jar file. You can further pipe through a sort to get unique jar files. For example,

java -verbose:class -version 2>/dev/null |
  sed -ne 's/\[Loaded \(.\+\) from \(.\+\)\]/\2/p' | 
  sort -u

outputs

/usr/local/jdk1.7.0_67/jre/lib/rt.jar
Nicholas Sushkin
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