// push InvocationHandler field
fv = cw.visitField(ACC_FINAL + ACC_PRIVATE, "invocationHandler", "Ljava/lang/reflect/InvocationHandler;", null, null);
fv.visitEnd();
// push constructor
mv = cw.visitMethod(ACC_PUBLIC, "<init>", "(Ljava/lang/reflect/InvocationHandler;)V", null, null);
mv.visitCode();
mv.visitVarInsn(ALOAD, 0);
mv.visitMethodInsn(INVOKESPECIAL, clsToOverride, "<init>", "()V");
mv.visitVarInsn(ALOAD, 0);
mv.visitVarInsn(ALOAD, 1);