public Class Delegater()//空參構造，該類管理委托實例并實現委托方法 //添加一個靜態方法委托，返回整型值ID代表該方法與參數構成的實例。若失敗，則返回-1。 public synchronized int addFunctionDelegate(Class<?> srcClass,String methodName,Object... params);//添加一個實例方法委托，返回整型值ID代表該方法與參數構成的實例。若失敗，則返回-1。 public synchronized int addFunctionDelegate(Object srcObj,String methodName,Object... params);//根據整型ID從委托實例中刪除一個方法委托,返回是否成功 public synchronized Boolean removeMethod(int registerID);//依次執行該委托實例中的所有方法委托（無序） public synchronized void invokeAllMethod();//將參數表轉換為參數類型表 private Class<?>[] getParamTypes(Object[] params);//由指定的Class、方法名、參數類型表獲得方法實例 private Method getDstMethod(Class<?> srcClass,String methodName,Class<?>[] paramTypes);class DelegateNode(Method refMethod,Object[] params)//DelegateNode類在不使用Object構造時敘述了一個靜態方法委托，包括方法實例及參數表 class DelegateNode(Object srcObj,Method refMethod,Object[] params)//DelegateNode類在使用Object構造時敘述了一個實例方法委托，包括類實例、方法實例及參數表 public void invokeMethod();//執行該節點敘述的方法委托

import java.lang.reflect.InvocationTargetException;import java.lang.reflect.Method;import java.util.Hashtable;/**Delegater類使用RTTI及反射實現Java下的委托機制  * @author 三向板磚  * */public class Delegater {	static int register = Integer.MIN_VALUE;	//ID分配變量 	Hashtable<Integer,DelegateNode> nodeTable;	//管理ID與對應委托的容器 	public Delegater() 	  {		nodeTable = new Hashtable<Integer,DelegateNode>();	}	//添加靜態方法委托 	public synchronized int addFunctionDelegate(Class<?> srcClass,String methodName,Object... params) 	  {		Class<?>[] paramTypes = getParamTypes(params);		Method refMethod;		if((refMethod = getDstMethod(srcClass,methodName,paramTypes)) != null) 		    {			register++;			nodeTable.put(register,new DelegateNode(refMethod, params));			return register;		} else 		    {			return -1;		}	}	//添加動態方法委托 	public synchronized int addFunctionDelegate(Object srcObj,String methodName,Object... params) 	  {		Class<?>[] paramTypes = getParamTypes(params);		Method refMethod;		if((refMethod = getDstMethod(srcObj.getClass(),methodName,paramTypes)) != null) 		    {			register++;			nodeTable.put(register,new DelegateNode(srcObj,refMethod, params));			return register;		} else 		    {			return -1;		}	}	//刪除一個方法委托 	public synchronized Boolean removeMethod(int registerID) 	  {		if(nodeTable.containsKey(registerID)) 		    {			nodeTable.remove(registerID);			return true;		}		return false;	}	//無序地執行委托方法 	public synchronized void invokeAllMethod() 	  {		for (DelegateNode node:nodeTable.values()) 		    {			node.invokeMethod();		}	}	//將參數表轉化為參數類型表 	private Class<?>[] getParamTypes(Object[] params) 	  {		Class<?>[] paramTypes = new Class<?>[params.length];		for (int i = 0;i < params.length;i++) 		    {			paramTypes[i] = params[i].getClass();		}		return paramTypes;	}	//根據Class類實例、方法名、參數類型表獲得一個Method實例 	private Method getDstMethod(Class<?> srcClass,String methodName,Class<?>[] paramTypes) 	  {		Method result = null;		try {			result = srcClass.getMethod(methodName, paramTypes);			if(result.getReturnType() != void.class) 			      {				System.out.println("Warning,Method:"+methodName+" has a return value!");			}		}		catch (NoSuchMethodException | SecurityException e) {			System.out.println("Can Not Found Method:"+methodName+",ensure it's exist and visible!");		}		return result;	}}class DelegateNode {	Object srcObj;	Method refMethod;	Object[] params;	public DelegateNode(Method refMethod,Object[] params) 	  {		this.refMethod = refMethod;		this.params = params;	}	public DelegateNode(Object srcObj,Method refMethod,Object[] params) 	  {		this.srcObj = srcObj;		this.refMethod = refMethod;		this.params = params;	}	public void invokeMethod() 	  {		try {			refMethod.invoke(srcObj,params);		}		catch (IllegalAccessException | IllegalArgumentException 		        | InvocationTargetException e) {			System.out.println("Method:"+refMethod.toString()+" invoke fail!");		}	}}

public class DelegaterTest {	public void showInfo() 	  {		System.out.println("Hello Delegate!");	}	public void showCustomInfo(String info) 	  {		System.out.println(info);	}	public static void showStaticInfo() 	  {		System.out.println("Static Delegate!");	}	public static void showCustomStaticInfo(String info) 	  {		System.out.println(info);	}	public static void main(String[] args) {		Delegater dele = new Delegater();		DelegaterTest tester = new DelegaterTest();		int ID = dele.addFunctionDelegate(tester,"showInfo");		dele.addFunctionDelegate(tester,"showCustomInfo","Custom!");		dele.addFunctionDelegate(DelegaterTest.class,"showStaticInfo");		dele.addFunctionDelegate(DelegaterTest.class,"showCustomStaticInfo","StaticCustom!");		dele.invokeAllMethod();		dele.removeMethod(ID);		System.out.println("------------------");		dele.invokeAllMethod();	}}