[编织消息框架][JAVA核心技术]动态代理应用8-IRpcReceive实现

     private static Map<Short, Map<Byte, Method>> RECEIVE_METHOD_INFO = new HashMap<>();

     public static <T> T registerReceiveProxy(Object obj) {
         Class<?> target = obj.getClass();
         if (target.isInterface()) {
             throw new RuntimeException("class is Interface : " + target);
         }
         QModel modelAnno = ReflectUtil.getAnno(target, QModel.class);
         String proxyClassName = target.getCanonicalName() + "$$receive$$";
         ClassPool classPool = JavassistHepler.classPool;
         CtClass ctClass = classPool.makeClass(proxyClassName);

         try {
             // 设置接口,继承 target
             CtClass[] interfaces = new CtClass[1];
             interfaces[0] = classPool.get(IRpcReceive.class.getName());
             ctClass.setInterfaces(interfaces);
             ctClass.setSuperclass(JavassistHepler.getCtClass(target));
             {
                 // 添加this字段
                 final String ctxName = target.getName();
                 CtField ctField = new CtField(classPool.get(ctxName), "_this", ctClass);
                 ctField.setModifiers(Modifier.PRIVATE | Modifier.FINAL);
                 // 添加json 忽略anno
                 ctField.getFieldInfo2().addAttribute(JavassistHepler.addAnno(JsonIgnore.class, ctClass));
                 ctClass.addField(ctField);
             }

             Map<Byte, Method> methods = new HashMap<>();
             RECEIVE_METHOD_INFO.put(modelAnno.value(), methods);

             // 生成代理方法
             ReflectUtil.foreachMethods(target, (method) -> {
                 QCommond commond = method.getAnnotation(QCommond.class);
                 if (commond == null) {
                     return;
                 }
                 methods.put(commond.value(), method);
                 String resultType = "";
                 if (void.class != method.getReturnType()) {
                     resultType = " return ($r) ";
                 }
                 final String body = "{ " + resultType + "_this." + method.getName() + "($$); }";
                 JavassistHepler.addMethod(ctClass, method, body);
             });

             // 生成receive method
             {
                 final String body = "{return ($r) " + QRpcFactory.class.getName() + ".proxyReceive(_this,$2, (short)" + modelAnno.value() + "  ,(byte) $1);}";
                 JavassistHepler.addMethod(ctClass, RECEIVE_METHOD, body);
             }

             // 添加构造方法 new XXProxy(XX)
             CtConstructor ctConstructor = new CtConstructor(JavassistHepler.toCtClassArray(target), ctClass);
             ctConstructor.setBody("{ this._this = $1; }");
             ctConstructor.setModifiers(Modifier.PUBLIC);
             ctClass.addConstructor(ctConstructor);
             Class<?> newClass = ctClass.toClass();
             Constructor<T> constructor = (Constructor<T>) newClass.getConstructor(target);
             constructor.setAccessible(true);
             ctClass.detach();
             Object ret = constructor.newInstance(obj);
             RECEIVE.put(modelAnno.value(), (IRpcReceive) ret);
             return (T) ret;
         } catch (Exception e) {
             throw new RuntimeException(e);
         }
     }

     // 因为 javassist $$ 表达式访问的 参数类型 为 object 获取不到目标类型，所以只能用 invoke 处理
     public static Object proxyReceive(Object target, Object[] args, short model, byte commondIndex) {
         Map<Byte, Method> methods = RECEIVE_METHOD_INFO.get(model);
         try {
             return methods.get(commondIndex).invoke(target, args);
         } catch (Exception e) {
             throw new QRpcException(QCode.ENHANCE_ERROR_RPC_NOFIND_MODEL, "proxyReceive ", e);
         }
     }
 }

    @Test
    public void testReceive() {
        TestObject proxy = QRpcFactory.registerReceiveProxy(new TestObjectImpl());

        proxy.a(1, "b");
        proxy.setAge(30);
        QResult<Integer> ret = proxy.getAge();
        System.out.println(ret.getResult());

        Object[] args = new Object[1];
        args[0] =18;

        ((IRpcReceive) proxy).receive((byte) 2, args);

        ret = proxy.getAge();
        System.out.println(ret.getResult());
        args[0] = new TestObject1();
        ((IRpcReceive) proxy).receive((byte) 4, args);
    }

    @Test
    public void testObjectArgs() {
        QRpcFactory.registerReceiveProxy(new TestObjectImpl());
        IRpcReceive obj = QRpcFactory.loadReceiveProxy((short)1);
        int a=30;
        Integer b= 30;
        double c=1d;
        List<Integer> d = new ArrayList<>();
        Integer[] e = new Integer[0];
        Object[] args = new Object[5];
        args[0] =a;
        args[1] =b;
        args[2] =c;
        args[3] =d;
        args[4] =e;

        obj.receive((byte)5, args);
    }

在实际开发时 因为 javassist $$ 表达式访问的参数类型为object 获取不到目标类型，编译时出现错误

Type 'java/lang/Object' (current frame, stack[1]) is not assignable to integer

所以只能用 invoke 处理