模拟买票练习多线程
- 使用Thread和Runable练习买票和练习共享资源问题
- 方式一：继承Thread类
-
1.首先定义一个ticks变量为总票数为10 -
2.定义run方法，循环的扣除票数量（简单写一下打印ticks票数） -
3.模拟四个窗口购买票 - 问题1：打印的结果是每个窗口都打印了10张票，也就是说变量tickets没有共享
- 解决1：通过给变量添加static，使变量变为共享变量如（代码1）
- 解决2：通过实现runable接口解决共享变量问题（代码2）
- 问题2：打印的ticks数量顺序不是从10->1，顺序乱了，也就是数据不同步
- 解决：通过代码块同步或者方法同步解决问题（加锁）（代码3、4）
代码1：
package com.lzw.java_thread.tickets;
/**
* 使用Thread和Runable练习买票和练习共享资源问题
* 方式一：继承Thread类
* 1.首先定义一个ticks变量为总票数为10
* 2.定义run方法，循环的扣除票数量（简单写一下打印ticks票数）
* 3.模拟四个窗口购买票
*/
public class ThreadTicks extends Thread{
private static int tickets = 10;
@Override
public void run() {
while (tickets>0){
try {
Thread.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
synchronized (this){
if (tickets>0){
System.out.println(Thread.currentThread().getName() + " 剩余" + (tickets--) + "张票");
}
}
}
}
public static void main(String[] args) {
ThreadTicks tt1 = new ThreadTicks();
ThreadTicks tt2 = new ThreadTicks();
ThreadTicks tt3 = new ThreadTicks();
ThreadTicks tt4 = new ThreadTicks();
tt1.start();
tt2.start();
tt3.start();
tt4.start();
}
}
代码2：
package com.lzw.java_thread.tickets;
/**
*第二种方式：
* 1.实现Runable接口
* 2.创建四个线程都传入一个Runable子类，实现对象资源共享
* 3.调用start()方法
*/
public class RunableTickets implements Runnable{
private int tickets = 10;
@Override
public void run() {
while (tickets>0){
try {
Thread.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (tickets>0){
System.out.println(Thread.currentThread().getName()+" 剩余"+(tickets--)+"张票");
}
}
}
public static void main(String[] args) {
RunableTickets rtt = new RunableTickets();
Thread td1 = new Thread(rtt);
Thread td2 = new Thread(rtt);
Thread td3 = new Thread(rtt);
Thread td4 = new Thread(rtt);
td1.start();
td2.start();
td3.start();
td4.start();
}
}
代码3：
package com.lzw.java_thread.tickets;
/**
* @Auther: lzw
* 使用同步代码块，实现共享资源同步
*/
public class RunableTickets1 implements Runnable{
private int tickets = 10;
@Override
public void run() {
while (tickets>0){
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
synchronized (this){
if (tickets>0){
System.out.println(Thread.currentThread().getName()+" 剩余"+(tickets--)+"张票");
}
}
}
}
public static void main(String[] args) {
RunableTickets1 rtt = new RunableTickets1();
Thread td1 = new Thread(rtt);
Thread td2 = new Thread(rtt);
Thread td3 = new Thread(rtt);
Thread td4 = new Thread(rtt);
td1.start();
td2.start();
td3.start();
td4.start();
}
}
代码4：
package com.lzw.java_thread.tickets;
/**
* @Auther: lzw
* 使用同步方法，实现共享资源同步
*/
public class RunableTickets2 implements Runnable{
private int tickets = 10;
@Override
public void run() {
while (tickets>0){
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
this.sale();
}
}
public synchronized void sale(){
if (tickets>0){
System.out.println(Thread.currentThread().getName()+" 剩余"+(tickets--)+"张票");
}
}
public static void main(String[] args) {
RunableTickets2 rtt = new RunableTickets2();
Thread td1 = new Thread(rtt);
Thread td2 = new Thread(rtt);
Thread td3 = new Thread(rtt);
Thread td4 = new Thread(rtt);
td1.start();
td2.start();
td3.start();
td4.start();
}
}