How to read, write file inside the JAR file?

Hi all,
I want to read the file inside the jar file, use following method:
File file = new File("filename");
It works if not in JAR file, but it doesn't work if it's in a JAR file.
I found someone had the same problem, but no reply.
http://forum.java.sun.com/thread.jsp?forum=22&thread=180618
Can you help me ? I have tried this for all night !
Thanks in advance
Leo

If you want to read a file from the JAR file that the
application is packaged in (rather than a separate
external JAR file) you do it like this ...
InputStream is =
ClassLoader.getSystemResourceAsStream("filename");Better to use
this.getClass().getClassLoader().getResourceAsStream();
From a class near to where the data is. This deals with multiple classloaders properly.

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How to read, write file inside the JAR file?

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