Comparing two .jar files

Question

How do I compare two .jar files? Both of them have compiled .class files.

I want the difference in terms of method changes, etc.

Answer 1

• JAPICC, sample usage:

  japi-compliance-checker OLD.jar NEW.jar

  Sample reports for log4j: http://abi-laboratory.pro/java/tracker/timeline/log4j/

  

• PkgDiff, sample usage:

  pkgdiff OLD.jar NEW.jar

  See sample report for args4j.

  

• Clirr, sample usage:

  java -jar clirr-core-0.6-uber.jar -o OLD.jar -n NEW.jar