在最近的專案開發中，在封裝業務層對外介面時，需要對所有的方法操作，例如捕獲自定義的異常訊息等，之後想到使用動態代理的方式進行處理，具體的Demo如下：
1、業務介面類和介面具體實現類
IGlobalService.java

public interface IGlobalService {
    void method1();
    void method2();
    void method3();
}

GlobalServiceImpl.java

public class GlobalServiceImpl implements IGlobalService {
 

    private static final String TAG = GlobalServiceImpl.class.getSimpleName();

    @Override
    public void method1() {
        Log.i(TAG,"method1()");
    }

    @Override
    public void method2() {
        Log.i(TAG,"method2()");
    }

    @Override
    public void method3() {
        Log.i(TAG,"method3()"
 
);
    }
}

2、呼叫處理器類
動態代理的實現，需要實現InvocationHandler，並且傳入被代理物件。

public class GlobalServiceDynamicProxy implements InvocationHandler {

    private static final String TAG = GlobalServiceImpl.class.getSimpleName();
    private  Object mProxied;//被代理的物件

    private GlobalServiceDynamicProxy(Object proxied){
        this
 
.mProxied = proxied;
    }

    static IGlobalService createServiceProxy(IGlobalService realImpl){
        //建立呼叫處理器物件
        GlobalServiceDynamicProxy proxy = new GlobalServiceDynamicProxy(realImpl);
        //獲取需要被代理的物件（IGlobalService型別的物件）的一組介面
        Class[] classes = realImpl.getClass().getInterfaces();
        //傳入被代理物件型別的ClassLoader、一組介面和呼叫處理器物件，生成動態物件
        IGlobalService serviceProxy = (IGlobalService) Proxy.newProxyInstance(IGlobalService.class.getClassLoader(),classes,proxy);
        return serviceProxy;
    }



    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        Log.i(TAG,"GlobalServiceProxy before invoke");
        method.invoke(mProxied,args);
        Log.i(TAG,"GlobalServiceProxy after invoke");
        return null;
    }
}

3、測試
GlobalServiceManager.java:

    public abstract  class GlobalServiceManager {

    private static IGlobalService sService;

    public static void init(){
        if(sService==null){
            sService = GlobalServiceDynamicProxy.createServiceProxy(new GlobalServiceImpl());
        }
    }

    public static IGlobalService getService(){
        if(sService==null){
            init();
        }
        return sService;
    }
}

ApplicationTest .java

public class ApplicationTest extends ApplicationTestCase<Application> {
    private IGlobalService mService;

    public ApplicationTest() {
        super(Application.class);
    }

    @Override
    protected void setUp() throws Exception {
        super.setUp();
        GlobalServiceManager.init();
        mService = GlobalServiceManager.getService();

    }

    public void testMethod1(){
        mService.method1();
    }
    public void testMethod2(){
        mService.method2();
    }
    public void testMethod3(){
        mService.method3();
    }
    }

4、測試執行結果
GlobalServiceProxy before invoke
GlobalServiceImpl: method1()
GlobalServiceImpl: GlobalServiceProxy after invoke
GlobalServiceImpl: GlobalServiceProxy before invoke
GlobalServiceImpl: method2()
GlobalServiceImpl: GlobalServiceProxy after invoke
GlobalServiceImpl: GlobalServiceProxy before invoke
GlobalServiceImpl: method3()
GlobalServiceImpl: GlobalServiceProxy after invoke