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why .class is not specified during execution

 
Varun Chopra
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If we have to execute a class Student.class, we run it as

java Student

question is, why do we omit .class extension while executing? Why not following:

java Student.class
 
Sid Murrey
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Just a wild guess.. The JVM takes all the .class files it finds in the directories specified by the classpath and stores them using the package and class name in a list. When you specify the class to execute, the JVM does not associate that class name with a specific file, but with the real class stored in memory?

Just thinking here.. No facts! Just what I would handle it as a JVM programmer ;-)
 
Rob Spoor
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Close; a class is only loaded when it is needed. But you are right that it uses the class name (including full package), and not the class file.

Of course it will read the file when the class is first needed, but that is handled by the ClassLoader after a request for a class (name) has come in.
 
Campbell Ritchie
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That's the way Java was designed. Might be because the people who designed it came from the Unix tradition of calling executable code by their names without an extension.

Apart from that, don't know. I have always looked on it as "one of those things."
 
Varun Chopra
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Thanks Friends.
 
It is sorta covered in the JavaRanch Style Guide.
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