生产者和消费者模型
三个生产者向一个内存容器中产生数据,另外三个消费者从容器中消费数据。
public class Main { public static void main(String[] args) throws Exception { //内存缓冲区 BlockingQueue<Data> queue = new LinkedBlockingQueue<Data>(10); //生产者 Provider p1 = new Provider(queue); Provider p2 = new Provider(queue); Provider p3 = new Provider(queue); //消费者 Consumer c1 = new Consumer(queue); Consumer c2 = new Consumer(queue); Consumer c3 = new Consumer(queue); //创建线程池运行,这是一个缓存的线程池,可以创建无穷大的线程,没有任务的时候不创建线程。空闲线程存活时间为60s(默认值) ExecutorService cachePool = Executors.newCachedThreadPool(); cachePool.execute(p1); cachePool.execute(p2); cachePool.execute(p3); cachePool.execute(c1); cachePool.execute(c2); cachePool.execute(c3); try { Thread.sleep(3000); } catch (InterruptedException e) { e.printStackTrace(); } p1.stop(); p2.stop(); p3.stop(); try { Thread.sleep(2000); } catch (InterruptedException e) { e.printStackTrace(); } // cachePool.shutdown(); // cachePool.shutdownNow(); } }
public class Provider implements Runnable{ //共享缓存区 private BlockingQueue<Data> queue; //多线程间是否启动变量,有强制从主内存中刷新的功能。即时返回线程的状态 private volatile boolean isRunning = true; //id生成器,因为多个producer共享这个变量 private static AtomicInteger count = new AtomicInteger(); //随机对象 private static Random r = new Random(); public Provider(BlockingQueue queue){ this.queue = queue; } public void run() { while(isRunning){ try { //随机休眠0 - 1000 毫秒 表示获取数据(产生数据的耗时) Thread.sleep(r.nextInt(1000)); //获取的数据进行累计... int id = count.incrementAndGet(); //比如通过一个getData方法获取了 Data data = new Data(Integer.toString(id), "数据" + id); System.out.println("当前线程:" + Thread.currentThread().getName() + ", 获取了数据,id为:" + id + ", 进行装载到公共缓冲区中..."); if(!this.queue.offer(data, 2, TimeUnit.SECONDS)){ System.out.println("提交缓冲区数据失败...."); //do something... 比如重新提交 } } catch (InterruptedException e) { e.printStackTrace(); } } } public void stop(){ this.isRunning = false; } }
public class Consumer implements Runnable{ private BlockingQueue<Data> queue; public Consumer(BlockingQueue queue){ this.queue = queue; } //随机对象 private static Random r = new Random(); public void run() { while(true){ try { //获取数据 Data data = this.queue.take(); //进行数据处理。休眠0 - 1000毫秒模拟耗时 Thread.sleep(r.nextInt(1000)); System.out.println("当前消费线程:" + Thread.currentThread().getName() + ", 消费成功,消费数据为id: " + data.getId()); } catch (InterruptedException e) { e.printStackTrace(); } } } }
public final class Data { private String id; private String name; public Data(String id, String name){ this.id = id; this.name = name; } public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } @Override public String toString(){ return "{id: " + id + ", name: " + name + "}"; } }