private void putMethodArgumentOnStack(MethodVisitor methodVisitor, Type type, int index) {
   methodVisitor.visitVarInsn(type.getOpcode(ILOAD), index);
 }
 private int returnCode(Type returnType) {
   return returnType.getOpcode(IRETURN);
 }
 private void putFirstMethodArgumentOnStack(MethodVisitor methodVisitor, Type argType) {
   int loadCode = argType.getOpcode(ILOAD);
   methodVisitor.visitVarInsn(loadCode, 1);
 }