Extracing jar file  Assuming JDK installed on your machine, use below command   jar xf {jar file to extract}   If it doesnt work, make sure {C:\Program Files\Java\jdk1.6.0_31\bin or JAVA_HOME } configured in your PATH environmental variable.  To edit environmental variable, in Windows7, Right Click on windows computer -- Properties -- Advanced System Settings -- Advanced Tab -- Environment Variables.    
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