Force outputstream to release resources?

im running my program from a jar file.
just for fun i create a FileOutputStream to that same jar file then close it. i dont write anything.
then when i try to instantiate a class from that jar i get a class not found error.
if no one can tell me why, can someone tell me where i can learn more about OutputStreams?

When you open a FileOuptStream and don't specify 'true' as a second argument in the constructor, it delete the existing file and then create a new empty one. As you can guess the second arguement is an append option.

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