Java多執行緒18 Producer and Consumer設計模式
摘要:
Java多執行緒目錄
public class ProducerThread extends Thread {
private final static Random random = new Random(System.currentTimeMi...
public class ProducerThread extends Thread { private final static Random random = new Random(System.currentTimeMillis()); private final static AtomicInteger counter = new AtomicInteger(0); private final MessageQueue messageQueue; public ProducerThread(MessageQueue messageQueue, int seq) { super("Producer-" + seq); this.messageQueue = messageQueue; } @Override public void run() { while (true) { try { Message message = new Message("Message-" + counter.getAndIncrement()); messageQueue.put(message); System.out.println(Thread.currentThread().getName() + " put message " + message.getData()); Thread.sleep(random.nextInt(1000)); } catch (InterruptedException e) { break; } } } }
public class ConsumerThread extends Thread { private final static Random random = new Random(System.currentTimeMillis()); private final MessageQueue messageQueue; public ConsumerThread(MessageQueue messageQueue, int seq) { super("Consumer-" + seq); this.messageQueue = messageQueue; } @Override public void run() { while (true) { try { Message message = messageQueue.take(); System.out.println(Thread.currentThread().getName() + " take a message " + message.getData()); Thread.sleep(random.nextInt(1000)); } catch (InterruptedException e) { break; } } } }
public class Message { public Message(String data) { this.data = data; } private String data; public String getData() { return data; } public void setData(String data) { this.data = data; } }
public class MessageQueue { private final static int DEFAULT_MAX_LIMIT = 100; private final LinkedList<Message> queue; private final int limit; public MessageQueue() { this(DEFAULT_MAX_LIMIT); } public MessageQueue(final int limit) { this.limit = limit; this.queue = new LinkedList<>(); } public void put(final Message message) throws InterruptedException { synchronized (queue) { while (queue.size() > limit) { queue.wait(); } queue.addLast(message); queue.notifyAll(); } } public Message take() throws InterruptedException { synchronized (queue) { while (queue.isEmpty()) { queue.wait(); } Message message = queue.removeFirst(); queue.notifyAll(); return message; } } public int getMaxLimit() { return this.limit; } public int getMessageSize() { synchronized (queue) { return queue.size(); } } }
public class ProducerAndConsumerClient { public static void main(String[] args) { final MessageQueue messageQueue = new MessageQueue(); new ProducerThread(messageQueue, 1).start(); new ProducerThread(messageQueue, 2).start(); new ProducerThread(messageQueue, 3).start(); new ConsumerThread(messageQueue, 1).start(); new ConsumerThread(messageQueue, 2).start(); } }
Producer-1 put message Message-0 Producer-3 put message Message-2 Producer-2 put message Message-1 Consumer-1 take a message Message-0 Consumer-2 take a message Message-1 Producer-2 put message Message-3 Consumer-1 take a message Message-2 Producer-2 put message Message-4 Consumer-2 take a message Message-3 Producer-3 put message Message-5 Producer-3 put message Message-6 Producer-3 put message Message-7 Consumer-1 take a message Message-4 Producer-2 put message Message-8 Consumer-2 take a message Message-5 Producer-3 put message Message-9 Producer-1 put message Message-10 Producer-1 put message Message-11 Producer-2 put message Message-12 省略...