任务型队列式多线程之实现
????? 前言：最近做的一个项目正好要用到多线程，而且要实现队列式处理，即外界可向线程添加任务，同时一旦队列中有任务时，线程自动启动对之进行处理。要求任务的添加与执行要同步处理。最终结果如下：
[TaskThread.java]
import java.util.HashMap;import java.util.Vector;/*** Task Processing Thread.It is enable to add Task and perform task synchronously.* All tasks is restored in the task queue.* If there is task(s) in the task queue,it(them) will be performed by the thread automaticlly.* Or the thread will be turned into waiting for waking.* <br>* Mode:Multiton Mode* <br>* 任务处理线程,实现同步添加及执行任务,任务保存在任务队列之中.* 当任务队列中存在任务时,线程将自动对其进行处理;否则线程进入等待状态.* <br>* 模式:多例模式* @author Micheal Hong* @email babala_234@163.com* @see Task*/public class TaskThread extends Thread{private static HashMap<String,TaskThread> instanceMap=new HashMap<String,TaskThread>();private Vector<Task> taskQueue=new Vector<Task>();private boolean runnable=true;/*** Return a task thread instance corresponding to threadId,* if it don't exist,create one and return it.* Note that each <code>threadId</code> is unique to the others.* <br>* 返回一个与threadId对应的任务处理线程实例,如果不存在这样的实例,* 则进行创建并返回一个新实例,新实例与threadId相对应* @param threadId* @return*/public static TaskThread getInstance(String threadId){ if(instanceMap.containsKey(threadId)==false) { instanceMap.put(threadId,new TaskThread()); } return instanceMap.get(threadId);}private TaskThread(){}@Overridepublic void run() { Task task; while(runnable) { synchronized (taskQueue) { //apply for the task queue's obj lock while(taskQueue.isEmpty()) { taskQueue.notify(); //release the task queue's obj lock try { taskQueue.wait(); //turn into waiting for being waken } catch (InterruptedException e) { e.printStackTrace(); } } /*when the task queue is not empty*/ task=taskQueue.remove(0); //fetch the head task taskQueue.notify(); //release the task queue's obj lock } task.perform(); //perform the task }}/*** Add task into task queue synchronously and then wake the task thread.* <br>* 向任务队列添加任务并唤醒线程对队列进行处理* @param task*/public void addTask(Task task){ synchronized (taskQueue) { //apply for the task queue's obj lock taskQueue.add(task); taskQueue.notify(); //release the task queue's obj lock }}}?[Task.java]
*** Task Entry* 任务实体* Mode:Template Mode* 模式:模板模式* @author Micheal Hong**/public abstract class Task {protected String projectId;public Task(String projectId){ this.projectId=projectId;}public String getProjectId() { return projectId;}/*** task performance.It is an interface supplied for implemented by caller.* 任务的执行。由调用者自行实现。* @see TaskThread*/public abstract void perform();}?
以上代码都已经过测试，呵呵，一个简单的线程雏形，希望对初学者有所帮助，算是抛砖引玉吧。