I am trying to modify the some 1000 class files ,my intension is to insert sys out while entering any method.

and replacing the class file using to byteCode.

Ex Code snippet:--

method.insertBefore(stringToBeInjected);

cc.writeFile();

cc.defrost();

byte[] bytes = cc.toBytecode();

FileOutputStream appendedFile = new FileOutputStream(file, false);

appendedFile.write(bytes);

appendedFile.close();

It is doing iteration for all 1000 class files or so files.