Java高级——交通灯管理系统

本方法模拟了现实生活中的交通信号灯的情况

1.先构建Road类，此类可以创建12个方向的路

代码如下：

 1 package com.springtie.traffic;
 2
 3 import java.util.ArrayList;
 4 import java.util.List;
 5 import java.util.Random;
 6 import java.util.concurrent.ExecutorService;
 7 import java.util.concurrent.Executors;
 8 import java.util.concurrent.ScheduledExecutorService;
 9 import java.util.concurrent.TimeUnit;
10
11 public class Road {
12     // 12个方向的路名
13     private String roadname;
14     // 存储车辆的集合
15     private List<String> vehicle = new ArrayList<String>();
16
17     // 根据每个方向的不同创建不同的路名
18     public Road(String roadname) {
19         this.roadname = roadname;
20         // 向当前路添加1000辆车
21         ExecutorService pool = Executors.newSingleThreadExecutor();
22         pool.execute(new Runnable() {
23             public void run() {
24                 try {
25                     Thread.sleep((new Random().nextInt(10) + 1) * 1000);
26                 } catch (InterruptedException e) {
27                     e.printStackTrace();
28                 }
29                 for (int car = 0; car < 1000; car++) {
30                     // 把车辆添加进来
31                     vehicle.add(roadname + "方向的车辆" + car);
32                     // System.out.println(roadname+"方向的车辆"+car+"正在开过来");
33                 }
34             }
35         });
36         // 当前路上的，灯位绿色的，使其最前面的车辆1秒后穿越马路，再过一秒后上来的最前面车辆穿越马路，如此循环，知道灯变红
37         ScheduledExecutorService timer = Executors.newScheduledThreadPool(1);
38         timer.scheduleAtFixedRate(new Runnable() {
39             public void run() {
40                 if (!vehicle.isEmpty()) {
41                     boolean lampState = Lamp.valueOf(roadname).isLighted();
42                     if (lampState) {
43
44                         System.out.println(vehicle.remove(0) + "穿越马路");
45                     }
46                 }
47             }
48         }, 1, 1, TimeUnit.SECONDS);
49     }
50 }

2.创建交通灯枚举Lamp，通过私有构造函数传入当前灯的对应灯和下一个灯以及当前的状态

代码如下：

 1 package com.springtie.traffic;
 2
 3 public enum Lamp {
 4     // 12个信号灯枚举对象
 5     S2N("N2S", "S2W", false), S2W("N2E", "E2W", false), E2W("W2E", "E2S", false), E2S(
 6             "W2N", "S2N", false), N2S(null, null, false), N2E(null, null, false), W2E(
 7             null, null, false), W2N(null, null, false), S2E(null, null, true), E2N(
 8             null, null, true), N2W(null, null, true), W2S(null, null, true);
 9     // 枚举私有成员变量
10     private String oppositeLamp;
11     private String nextLamp;
12     private boolean lampState;
13
14     // 私有构造函数
15     private Lamp(String oppositeLamp, String nextLamp, boolean lampState) {
16         this.oppositeLamp = oppositeLamp;
17         this.nextLamp = nextLamp;
18         this.lampState = lampState;
19     }
20
21     // 判断是红灯还是绿灯
22     public boolean isLighted() {
23         return lampState;
24     }
25
26     // 让灯变绿，对应灯也变绿
27     public void turnGreen() {
28         this.lampState = true;
29         if (oppositeLamp != null) {
30             Lamp.valueOf(oppositeLamp).turnGreen();
31         }
32         System.out.println("灯：" + this.name() + "为绿灯，+对应等和其他四个灯也为绿灯");
33     }
34
35     // 让灯和对应灯变红，同时让下一个灯变绿，返回下一个灯
36     public Lamp turnRed() {
37         this.lampState = false;
38         if (oppositeLamp != null) {
39             Lamp.valueOf(oppositeLamp).turnRed();
40         }
41         Lamp next = null;
42         if (nextLamp != null) {
43             next = Lamp.valueOf(nextLamp);
44             System.out.println("绿灯：" + this.name() + "    切换为：" + next.name());
45             next.turnGreen();
46         }
47         return next;
48     }
49 }

3.创建灯控系统类LampController，利用此类来控制灯变量的顺序

代码如下：

 1 package com.springtie.traffic;
 2
 3 import java.util.concurrent.Executors;
 4 import java.util.concurrent.ScheduledExecutorService;
 5 import java.util.concurrent.TimeUnit;
 6
 7 public class LampController {
 8     private Lamp currentLamp;
 9
10     public LampController() {
11         currentLamp = Lamp.S2N;
12         // 让当前灯变绿
13         currentLamp.turnGreen();
14         // 单开一个线程，当前灯变红的同时下个等变绿，一直重复
15         ScheduledExecutorService timer = Executors.newScheduledThreadPool(1);
16         timer.scheduleAtFixedRate(new Runnable() {
17             public void run() {
18                 System.out.println("当前灯变红时，返回下个灯并让其变绿");
19                 currentLamp = currentLamp.turnRed();
20             }
21         }, 10, 10, TimeUnit.SECONDS);
22     }
23 }

4.创建一个主类（MainClass）来测试

代码如下：

 1 package com.springtie.traffic;
 2
 3 public class MainClass {
 4
 5     public static void main(String[] args) {
 6         // 代表12条路的方向
 7         String[] directionRoadName = new String[] { "S2N", "S2W", "E2W", "E2S",
 8                 "N2S", "N2E", "W2E", "W2N", "S2E", "E2N", "N2W", "W2S" };
 9         // 把12条路的线程启动
10         for (int i = 0; i < directionRoadName.length; i++) {
11             new Road(directionRoadName[i]);
12         }
13         // 调用灯控系统
14         new LampController();
15     }
16
17 }

至此，一个完整的模拟现实生活中的交通灯管理系统构建完毕。