Manifest file in executable jars

You might have encountered following error message when trying to run an executable jar file.

Code:

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Java Virtual Machine Launcher
Could not find the main class. Program will exit!

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This occurs because Manifest file is either missing or dose not contain the class name which has the main method.

Code:

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Manifest-Version: 1.2
Main-Class: MainClassName
Created-By: 1.4 (Sun Microsystems Inc.)

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