A Cool open source software I found on internet it can search a .class file from a bunch of .jar files. Download jarscan.jar from below link... Usage: To display the help message type: java -jar jarscan.jar -help OR java -jar jarscan.jar To find the class ArrayList starting from the root of your c: drive type: java -jar jarscan.jar -dir c:\ -class ArrayList Here is the URL, http://www.inetfeedback.com/jarscan/