关于ExecutorService 的用法

package my;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;


public class Test {

    public static void main(String[] args) throws InterruptedException {
        final List sList = Collections.synchronizedList(new ArrayList<Student>());
        ExecutorService service = Executors.newFixedThreadPool(20);
        for(int i = 0;i<20;i++){
            final int finali = i;
            service.submit(new Runnable() {
                @Override
                public void run() {
                    sList.add(new Student("a", finali));
                }
            });
        }
        service.shutdown();
        service.awaitTermination(Long.MAX_VALUE, TimeUnit.DAYS);
        for(Object s:sList){
            System.out.println(((Student)s).getName()+" "+((Student)s).getAge());
        }
    }
}

注意：shutdown()之后的代码并不会等待线程执行完后再执行，需要使用awaitTermination函数等待所有线程执行完成