采用多线程技术，例如wait/notify，设计实现一个符合生产者和消费者问题的程序，对某一个对象（枪膛）进行操作，其最大容量是20颗子弹，生产者线程是一个压入线程，它不断向枪膛中压入子弹，消费者线程是一个射出线程，它不断从枪膛中射出子弹。

package com.kelley;public class Demo052901 {public  static final Integer MAX_SIZE = 20;public  static final Integer MIN_SIZE = 0;private static class Gun{private int num;synchronized void input() {try {while (num >= MAX_SIZE) {System.err.println("弹匣已满，无法装弹");wait();}num ++;System.out.println("弹匣未满，开始装弹，现有子弹:" + num);notifyAll();} catch (InterruptedException e) {e.printStackTrace();}}synchronized void output() {try {while (num <= MIN_SIZE) {System.err.println("弹匣已空，无法射击");wait();}System.out.println("弹匣有弹，开始射击，现有子弹:" + num);num --;System.out.println("射击完还剩子弹:" + num);notifyAll();} catch (InterruptedException e) {e.printStackTrace();}}}private static class Input implements Runnable{public Gun gun;public Input(Gun gun){this.gun = gun;}@Overridepublic void run() {while(true){gun.input();}}}private static class Output implements Runnable{public Gun gun;public Output(Gun gun){this.gun = gun;}@Overridepublic void run() {while(true){gun.output();}}}public static void main(String[] args) {Gun gun = new Gun();Thread threadInput = new Thread(new Input(gun));threadInput.start();Thread threadOutput = new Thread(new Output(gun));threadOutput.start();}}