java 多线程-实现Callable接口

• 实现callable接口加泛型，即返回的值类型，默认为Object

• 重写的call方法可以有返回值，可以抛出异常

  public class ThreadDownload implements Callable<Boolean> {

  public Boolean call() throws Exception
  {

  return true;

  }
  public static void main(String[]args) throws InterruptedException, ExecutionException
  {
  ThreadDownload a=new ThreadDownload();
  ThreadDownload b=new ThreadDownload();
  ThreadDownload c=new ThreadDownload();
  //创建执行服务
  ExecutorService ser =Executors.newFixedThreadPool(3);
  //提交执行
  Future<Boolean>result1=ser.submit(a);
  Future<Boolean>result2=ser.submit(b);
  Future<Boolean>result3=ser.submit(c);
  //获取结果
  boolean r1=result1.get();
  boolean r2=result2.get();
  boolean r3=result3.get();
  //关闭服务:
  ser.shutdownNow();
  }
  }