Help reading java bytecode

I need read java bytecode to understand the structure of a class. I need know the variable and the method of a class.
I do this using the library javassist. I would like to know wich method are called inside a method. I think I should interpratate the javabytecode. Is it technical possible do this? Any idea o useful link to read?
Edited by: orsvon on Sep 10, 2010 5:02 AM

Thanks for your useful link!
I get the method called inside a method using javap -c ClassFileName. Then I parse the output looking for the instraction invokevirtual.
Is there a clen way to do this?

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int loser_count = 0;
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Dallas 5 2
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Washington 3 4
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import java.io.*;
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FileInputStream fin = null; // input file reference
PrintStream floser = null; // output file references
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rs = new Scanner( fin );
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I fixed it.
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Help reading java bytecode

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