[Java基础] java多线程关于消费者和生产者
多线程: 生产与消费
1.生产者Producer生产produce产品,并将产品放到库存inventory里;同时消费者Consumer从库存inventory里消费consume产品。
2.库存inventory的总量(最大库存量100)是有限的。如果库存inventory满了,生产者不能在库存inventory继续生产produce产品,须等待状态。等待产品被消费者Consumer消费consume了,再往库存inventory生产produce产品。
3.若库存inventory空了,消费者Consumer也须等待状态。等待生产者生产produce产品,再将消费者Consumer唤醒进行消费consume。
补充要求:需要6个线程,分别实现
1.库存为0;2.消费1消费10个(但库存零,则需等待);3.生产2生产5个;4.生产3生产5个(此时库存有10个,则满足消费1的消费;)最终库存仍有0个;5.生产4生产100个);6.生产5生产10个(因库存满了,无法生产,需等待)
import java.util.concurrent.BlockingQueue; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.LinkedBlockingQueue; public class BlockingQueueTest { public static void main(String[] args) { ExecutorService service = Executors.newCachedThreadPool(); BlockingQueue<String> blockingQueue = new LinkedBlockingQueue<String>(100); System.out.println("blockingQueue now contains " + blockingQueue.size() + " unit"); service.submit(new Consumer1(blockingQueue)); gap(blockingQueue); service.submit(new Productor2(blockingQueue)); gap(blockingQueue); service.submit(new Productor3(blockingQueue)); gap(blockingQueue); service.submit(new Productor4(blockingQueue)); gap(blockingQueue); service.submit(new Productor5(blockingQueue)); gap(blockingQueue); service.shutdown(); } private static void gap(BlockingQueue<String> blockingQueue) { try { Thread.sleep(1000); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println("blockingQueue now contains " + blockingQueue.size() + " unit"); } } class Consumer1 implements Runnable{ BlockingQueue<String> blockingQueue; public Consumer1(BlockingQueue<String> blockingQueue) { super(); this.blockingQueue = blockingQueue; } @Override public void run() { // TODO Auto-generated method stub System.out.println("Consumer1 start: need 10 units"); for(int i = 0; i < 10; i++){ try { blockingQueue.take(); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } System.out.println("Consumer1 end: has got 10 units"); } } class Productor2 implements Runnable{ BlockingQueue<String> blockingQueue; public Productor2(BlockingQueue<String> blockingQueue) { super(); this.blockingQueue = blockingQueue; } @Override public void run() { // TODO Auto-generated method stub System.out.println("Productor2 start: put 5 units"); for(int i = 0; i < 5; i++){ try { blockingQueue.put("Object"); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } System.out.println("Productor2 end: has put 5 units"); } } class Productor3 implements Runnable{ BlockingQueue<String> blockingQueue; public Productor3(BlockingQueue<String> blockingQueue) { super(); this.blockingQueue = blockingQueue; } @Override public void run() { // TODO Auto-generated method stub System.out.println("Productor3 start: put 5 units"); for(int i = 0; i < 5; i++){ try { blockingQueue.put("Object"); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } System.out.println("Productor3 end: has put 5 units"); } } class Productor4 implements Runnable{ BlockingQueue<String> blockingQueue; public Productor4(BlockingQueue<String> blockingQueue) { super(); this.blockingQueue = blockingQueue; } @Override public void run() { // TODO Auto-generated method stub System.out.println("Productor4 start: put 100 units"); for(int i = 0; i < 100; i++){ try { blockingQueue.put("Object"); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } System.out.println("Productor4 end: has put 100 units"); } } class Productor5 implements Runnable{ BlockingQueue<String> blockingQueue; public Productor5(BlockingQueue<String> blockingQueue) { super(); this.blockingQueue = blockingQueue; } @Override public void run() { // TODO Auto-generated method stub System.out.println("Productor5 start: put 10 units"); for(int i = 0; i < 100; i++){ try { blockingQueue.put("Object"); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } System.out.println("Productor5 end: has put 10 units"); } }
每个线程是隔了1s启动的, 结果
blockingQueue now contains 0 unit
Consumer1 start: need 10 units
blockingQueue now contains 0 unit
Productor2 start: put 5 units
Productor2 end: has put 5 units
blockingQueue now contains 0 unit
Productor3 start: put 5 units
Productor3 end: has put 5 units
Consumer1 end: has got 10 units
blockingQueue now contains 0 unit
Productor4 start: put 100 units
Productor4 end: has put 100 units
blockingQueue now contains 100 unit
Productor5 start: put 10 units
blockingQueue now contains 100 unit