java-日志服务使用多线程

1、写入日志的活动作为生产者，读取日志的活动做为消费者。

2、保证创建新日志消息的各个子任务是原子的。但不希望在消息加入队列时加锁，即将put方法和take方法放在同步之外。

public class LogService{

   private finalBlockingQueue<String> queue;

   privatefinal LoggerThread loggerThread;

   private final PrintWriterwriter;

   @GuardBy("this") privateboolean isShutdown;

   @GuardBy("this")private intreservations;  

  

   public vidstart(){loggerThread.start();}

   public viod stop(){

      syndhronized (this) (isShutdown=true;)

      loggerThread.interrupt();

   }

  

   public void log(String msg)throws InterruptedException{

      synchronized (this){

          if (isShutdown) throws newIllegalStateException(...);++revations;

      }

      queue.put(msg);

   }

  

   private class loggerThreadextends Thread{

        public void run(){

             try{

                   while (true){

                      try{

                            synchronized (LogService.this){

                                 if (isShutdown&&reservations==0)break;

                            }

                      }

                   }catch (InterruptedException e){}

             }

        }

        finally{

                 writer.close();

        }

   }

  

 

}

3、封装ExecutorService通过增加链接，把所有权链从应用程序扩展到了服务，再到线程；每个链上的成员管理它的拥有的服务或线程的生命周期

public class Logservice{

    privatefinal ExecutorService exec=newSingleThreadExecutor();

    ...

    publicvoid start(){}

   

    publicvoid stop() throws InterruptedException{

       try{

         exec.shutdown();

         exec.awaitTermination(TIMEOUT,UNIT);

       }

       finally{

            writer.close();

        }

    }

    publicvoid log(String msg){

            try{

             }

              catch(RejectedExecutionException ignored) {}

    }

}

4、 一个可识别的对象，置于队列中，意味着当你得到它时，停止一切工作。