// now do byte code manipulation
final String fileName = outputDirectory + File.separatorChar + className.replace('.', File.separatorChar) + ".class";
final ClassNode cn = new ClassNode();
try {
final ClassReader reader = new ClassReader(new FileInputStream(fileName));
reader.accept(cn, 0);
// For target Java7 and above use: ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES
final int mask = (cn.version > 50 ? ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES : 0);
final ClassWriter writer = new ClassWriter(mask) {