The jar.exe utility program is distributed with the Java SDK, so if you 
installed the Java SDK (which you need to compile), you have the jar utility at 
your disposal.  Like all other Java SDK utilities, it is in the 
<java_install_dir>\bin directory.
 
Here is a summary of the syntax for using the jar utility for Windows and 
Solaris:
 
To view the contents of a jar file:
---------------------------------------------
jar tvf <jarfilename>
 
One page at a time:
jar tvf <jarfilename> | more
 
Looking for a certain class (Windows):
jar tvf <jarfilename> | find /I "<classname>"
 
Looing for a certain class (Solaris)
jar tvf <jarfilename> | grep -i <classname>
 
Explanation:  the "t" argument asks for a Table of Contents.  
The "v" argument requests Verbose mode.  
The "f" argument instructs the utility to perform these operations on a file to 
be supplied, not on stdin (console input)
 
To "explode" a jar file:
jar xvf <jarfilename>
 
Explanation:  the "x" argument specifies an Extract operation.  
The "v" argument requests Verbose mode.  
The "f" argument instructs the utility to perform these operations on a file to 
be supplied, not on stdin (console input).  The jar file is always exploded in 
the current directory.   Files that were added to the jar file in subdirectories
(for example class files that were in directories mimicking their package 
structure) will have those subdirectories recreated automatically.
 
The Windows version of jar is a little more forgiving.  For instance, if you 
call it like:

jar -xvf myjar.jar
 
Passing the "-" before the first switch out of habit; it will forgive you.  
The Solaris version won't (or didn't)