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

In Linux/CygWin a handy script I use at times is:

#Extract the jar (war or ear)
cd dir1
jar xvf jar-file1
for i in `ls *.class`
do
 javap $i > ${i}.txt #list the functions/variables etc
done

cd dir2
jar xvf jar-file2
for i in `ls *.class`
do
 javap $i > ${i}.txt #list the functions/variables etc
done

diff -r dir1 dir2 #diff recursively