read class file and write out into another file

package t;



import java.io.FileOutputStream;
import java.io.IOException;

import org.objectweb.asm.ClassAdapter;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.ClassWriter;

public class CopyClass {


	public static void main(String[] args) throws Exception {
		ClassWriter out=new ClassWriter(0);
		ClassVisitor cv=new ClassAdapter(out);
		ClassReader cr=new ClassReader("HelloWorld");
		cr.accept(cv, 0);
		output("/tmp/HelloWorld.class",  out.toByteArray());
	}

	public static void output(String filename, byte[] data) throws IOException {
		FileOutputStream out=new FileOutputStream(filename);
		out.write(data);
		out.close();
	}
}