作业

package threadlocal;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ThreadLocalHomework {
    //创建线程池
    public static ExecutorService threadPool= Executors.newFixedThreadPool(20);

    //创建线程要执行的方法
    public String data(int num){
        //清除之前线程访问的数据
        ThreadSafeStringBuilder.stringBuilderThreadLocal.remove();
        //获取每个线程要获取的对象
        StringBuilder stringBuilder=ThreadSafeStringBuilder.stringBuilderThreadLocal.get();
        //清除之前的数据
        stringBuilder.delete(0,stringBuilder.length());
        //添加数据
        return  stringBuilder.append("数字"+num).toString();
    }
    //测试
    public static void main(String[] args) {
        //20个请求
         for(int i=0;i<20;i++){
             int count=i;
           threadPool.execute(new Runnable() {
               @Override
               public void run() {
                   try {
                       Thread.sleep(1000);
                   } catch (InterruptedException e) {
                       e.printStackTrace();
                   }
                   //执行添加数据方法
                 String result= new ThreadLocalHomework().data(count);
                   System.out.println(result);
               }
           });
         }
         //关闭线程
        threadPool.shutdown();
        System.out.println("是否关闭:"+threadPool.isShutdown());
    }

}


//生成创建threadlocal类
class ThreadSafeStringBuilder{
    public static ThreadLocal<StringBuilder> stringBuilderThreadLocal
            =new ThreadLocal<StringBuilder>(){
        @Override
        protected StringBuilder initialValue() {
            return new StringBuilder();
        }
    };
}

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