中山快速建站合作,长沙外贸网站建设,怎么做轴承网站,360免费体育直播一、概述 1.目标#xff1a;把Proxy修改成可以代理任意接口及其任意方法 2.思路#xff1a; (1)代理任意接口#xff1a;把接口类型作为参数传给Proxy的newProxyInstance(Class interfze) (2)代理任意方法#xff1a;用interfze.getMethods()取出所有方法#xff0c;拼接实…一、概述 1.目标把Proxy修改成可以代理任意接口及其任意方法 2.思路 (1)代理任意接口把接口类型作为参数传给Proxy的newProxyInstance(Class interfze) (2)代理任意方法用interfze.getMethods()取出所有方法拼接实现方法的字符串   二、代码 1.Movable.java 2.Tank.java 3.Proxy.java 4.Client.java   1.Movable.java 1 package proxy; 2 3 public interface Movable { 4 public void move(); 5 public void stop(); 6 }   2.Tank.java 1 package proxy;2 3 import java.util.Random;4 5 public class Tank implements Movable {6 7 Override8 public void move() {9 System.out.println(Tank moving.......); 10 try { 11 Thread.sleep(new Random().nextInt(2000)); 12 } catch (InterruptedException e) { 13 e.printStackTrace(); 14 } 15 } 16 17 Override 18 public void stop() { 19 System.out.println(Tank stopping.......); 20 21 } 22 23 }   3.Proxy.java 1 package proxy;2 3 import java.io.File;4 import java.io.FileWriter;5 import java.lang.reflect.Constructor;6 import java.lang.reflect.Method;7 import java.net.URL;8 import java.net.URLClassLoader;9 10 import javax.tools.JavaCompiler; 11 import javax.tools.JavaCompiler.CompilationTask; 12 import javax.tools.StandardJavaFileManager; 13 import javax.tools.ToolProvider; 14 15 public class Proxy { 16 17 public static Object newProxyInstance(Class interfze) throws Exception { 18 19 String rt \n\r; 20 21 //拼接实现接口方法的字符串 22 String methodStr ; 23 for(Method m: interfze.getMethods() ){ 24 25 //取出方法的修饰符和返回值类型 26 String [] parts m.toString().replace(abstract , ).split(\\.); 27 String [] parts2 parts[0].split( ); 28 29 methodStr 30 Override rt 31 parts2[0] parts2[1] m.getName()() { rt 32 System.out.println(\Time Proxy start...........\); rt 33 long start System.currentTimeMillis(); rt 34 m. m.getName() (); rt 35 long end System.currentTimeMillis(); rt 36 System.out.println(\花费时间\(end - start)); rt 37 System.out.println(\Time Proxy end...........\); rt 38 } ; 39 } 40 41 42 //动态代理文件的源码 43 String str 44 package proxy; rt 45 46 public class TankTimeProxy implements interfze.getName() {rt 47 48 private interfze.getName() m; rt 49 50 public TankTimeProxy( interfze.getName() m) { rt 51 this.m m; rt 52 } rt 53 54 methodStr rt 55 56 } ; 57 58 //把源码写到java文件里 59 File file new File(System.getProperty(user.dir)/src/proxy/TankTimeProxy.java); 60 FileWriter fw new FileWriter(file); 61 fw.write(str); 62 fw.flush(); 63 fw.close(); 64 65 //编译源码生成class,注意编译环境要换成jdk才有compiler,单纯的jre没有compiler会空指针错误 66 JavaCompiler jc ToolProvider.getSystemJavaCompiler(); 67 68 //文件管事器 69 StandardJavaFileManager fileMgr jc.getStandardFileManager(null, null, null); 70 71 //编译单元 72 Iterable units fileMgr.getJavaFileObjects(file); 73 74 //编译任务 75 CompilationTask t jc.getTask(null, fileMgr, null, null, null, units); 76 77 //编译 78 t.call(); 79 fileMgr.close(); 80 81 //把类load到内存里 82 URL[] urls new URL[] {new URL(file:/System.getProperty(user.dir)/src/proxy/TankTimeProxy.class)}; 83 URLClassLoader uc new URLClassLoader(urls); 84 Class c uc.loadClass(proxy.TankTimeProxy); 85 86 //生成实例 87 //return c.newInstance(); //c.newInstance()会调用无参数的Construtor若类没有无参的Constructor时会出错 88 Constructor ctr c.getConstructor(interfze); 89 return ctr.newInstance(new Tank()); 90 } 91 }   4.Client.java 1 package proxy;2 3 import java.io.IOException;4 5 import org.junit.Test;6 7 public class Client {8 9 Test 10 public void testProxy() throws Exception{ 11 12 Movable m (Movable)Proxy.newProxyInstance(Movable.class); 13 m.move(); 14 m.stop(); 15 16 } 17 }   三、运行结果 转载于:https://www.cnblogs.com/shamgod/p/4592359.html