实现Callable接口，静态代理模式
作者：互联网
模拟龟兔赛跑的测试代码：
//模拟龟兔赛跑
public class Race implements Runnable {
//胜利者
private static String winner;
@Override
public void run() {
for (int i = 0; i <= 100; i++) {
//模拟兔子休息
if(Thread.currentThread().getName().equals("兔子") && i%10==0){
try {
Thread.sleep(1/10);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
//判断比赛是否结束
boolean flag = gameOver(i);
//如果比赛结束了，就停止程序
if(flag==true){
break;
}
System.out.println(Thread.currentThread().getName()+"--->跑了"+i+"步");
}
}
//判断是否完成比赛
private boolean gameOver(int steps){
//判断是否有胜利者
if(winner!=null){//已经存在胜利者了
return true;
}{
if(steps >= 100){
winner = Thread.currentThread().getName();
System.out.println("winner is " + winner);
return true;
}
}
return false;
}
public static void main(String[] args) {
Race race = new Race();
new Thread(race,"兔子").start();
new Thread(race,"乌龟").start();
}
}
实现Callable接口
-
实现Callable接口，需要返回值类型
-
重写call方法，需要抛出异常
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创建目标对象
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创建执行服务：ExecutorService ser = Executors.newFixedThreadPool(1);
-
提交执行：Future<Boolean> result1 = ser.submit(t1);
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获取结果：boolean r1 = result1.get();
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关闭服务：ser.shutdownNow();
Callable测试代码：
//线程创建方式三，实现Callable接口
/*
Callable的好处
1.可以定义返回值
2.可以抛出异常
*/
public class TestCallable implements Callable<Boolean> {
private String url; //网络图片地址
private String name; //保存的文件名
public TestCallable(String url,String name){
this.url = url;
this.name = name;
}
@Override
public Boolean call() {
WebDownloader webDownloader = new WebDownloader();
webDownloader.downloader(url,name);
System.out.println("下载了文件名为:"+name);
return true;
}
public static void main(String[] args) throws ExecutionException, InterruptedException {
TestCallable t1 = new TestCallable("https://imgessl.kugou.com/uploadpic/softhead/240/20220602/20220602093222410.jpg","1.jpg");
TestCallable t2 = new TestCallable("https://imgessl.kugou.com/uploadpic/softhead/240/20220602/20220602093222410.jpg","2.jpg");
TestCallable t3 = new TestCallable("https://imgessl.kugou.com/uploadpic/softhead/240/20220602/20220602093222410.jpg","3.jpg");
//创建执行服务：
ExecutorService ser = Executors.newFixedThreadPool(3);
//提交执行：
Future<Boolean> r1 = ser.submit(t1);
Future<Boolean> r2 = ser.submit(t2);
Future<Boolean> r3 = ser.submit(t3);
//获取结果：
boolean rs1 = r1.get();
boolean rs2 = r2.get();
boolean rs3 = r3.get();
System.out.println(rs1);
System.out.println(rs2);
System.out.println(rs3);
//关闭服务：
ser.shutdownNow();
}
}
//下载器
class WebDownloader{
//下载方法
public void downloader(String url, String name){
try {
FileUtils.copyURLToFile(new URL(url),new File(name));
} catch (IOException e) {
e.printStackTrace();
System.out.println("IO异常,downloader方法出现问题");
}
}
}
静态代理模式
静态代理模式测试代码：
//静态代理模式总结：
//真实对象和代理对象都要实现 同一个接口
//代理对象要代理真实角色
//好处：
//代理对象可以做很多真实对象做不了的事情
//真实对象专注自己的事情
public class StaticProxy {
public static void main(String[] args) {
You you = new You();//你要结婚
new Thread( ()-> System.out.println("喜欢你")).start();
new WeddingCompany(new You()).HappyMarry();
// WeddingCompany weddingCompany = new WeddingCompany(you);
// weddingCompany.HappyMarry();
}
}
interface Marry{
void HappyMarry();
}
//真实角色
class You implements Marry{
@Override
public void HappyMarry() {
System.out.println("要结婚了");
}
}
//代理角色，帮助你结婚
class WeddingCompany implements Marry{
//--->真实目标角色
private Marry target;
public WeddingCompany(Marry target) {
this.target = target;
}
@Override
public void HappyMarry() {
before();
this.target.HappyMarry();//这就是真实对象
after();
}
private void after() {
System.out.println("结婚之后，收尾款");
}
private void before() {
System.out.println("结婚之前，布置现场");
}
}
标签：静态,void,System,接口,Callable,println,new,public,out 来源： https://www.cnblogs.com/mhy123/p/16396977.html