Android 线程处理

synchronized处理线程wait() 和notifyAll() 时，同步代码块中不要包含Thread.sleep(5)语句：

  1 package com.csizg.test;
  2 
  3 
  4 import java.util.ArrayList;
  5 import java.util.List;
  6 
  7 /**
  8  * 与芯片交互线程
  9  */
 10 public class SpiQueue implements Runnable {
 11 
 12     private static final String TAG = SpiQueue.class.getSimpleName();
 13 
 14     private static final byte INIT = 0;// 初始化
 15     private static final byte RUNNING = 1;// 执行中
 16     private static final byte WITING = 2;// 暂停等待中
 17     private static final byte DONE = 3;// 结束
 18 
 19     private byte state = INIT;// 执行状态
 20 
 21     private static SpiQueue spiQueue = null;
 22     private boolean isTalking = false;
 23 
 24     private SpiQueue() {
 25 
 26     }
 27 
 28     public static SpiQueue getSpiQueue() {
 29         if (spiQueue == null) {
 30             spiQueue = new SpiQueue();
 31         }
 32         return spiQueue;
 33     }
 34 
 35     private Thread thread;
 36     private List<SpiTask> tasks = new ArrayList<>();
 37 
 38     @Override
 39     public void run() {
 40         state = RUNNING;
 41         while (state != DONE) {
 42 
 43                 SpiTask currentTask = getNextTask();
 44                 if (currentTask == null) {
 45                     if (isTalking) {
 46                         System.out.println(TAG + "  run  " + "no task todo begin to sleep");
 47                         try {
 48                             Thread.sleep(5);
 49                         } catch (InterruptedException e) {
 50                             e.printStackTrace();
 51                         }
 52                         continue;
 53                     } else {
 54                         System.out.println(TAG + "  run  " + "no task todo begin to waiting");
 55                         synchronized (this) {
 56                             try {
 57                                 state = WITING;
 58                                 wait();
 59                             } catch (InterruptedException e) {
 60                                 e.printStackTrace();
 61                             }
 62                         }
 63                     }
 64                 } else {
 65                     try {
 66                         Thread.sleep(10);
 67                     } catch (InterruptedException e) {
 68                         e.printStackTrace();
 69                     }
 70                     System.out.println(TAG + "  run  " + "currentTask = " + currentTask.toString());
 71                 }
 72 
 73         }
 74 
 75     }
 76 
 77     private synchronized SpiTask getNextTask() {
 78         System.out.println(TAG + "  getNextTask  " + "tasks.size() = " + tasks.size());
 79         if (tasks.size() > 0) {
 80             SpiTask task = tasks.remove(0);
 81             return task;
 82         }
 83         return null;
 84     }
 85 
 86     public synchronized void addTask(SpiTask task) {
 87         System.out.println(TAG + "  addTask  " + "tasks.size() = " + tasks.size() + ", new task : " + task.getCode());
 88         if (state == DONE) {
 89             System.out.println(TAG + "  addTask  " + "Thread is DONE : task : " + task.getCode());
 90             return;
 91         }
 92         tasks.add(task);
 93         if (state != RUNNING) {
 94             synchronized (this) {
 95                 state = RUNNING;
 96                 System.out.println(TAG + "  addTask notifyAll ");
 97                 notifyAll();
 98             }
 99         }
100     }
101 
102     public synchronized void start() {
103         System.out.println(TAG + "   start   " + "state = " + state);
104         if (state == RUNNING || state == WITING) {
105             return;
106         }
107         state = INIT;
108         // 运行本线程
109         tasks.clear();
110         if (thread != null) {
111             thread.interrupt();
112         }
113         thread = new Thread(this);
114         thread.start();
115     }
116 
117 
118     public synchronized void stop() {
119         state = DONE;
120         tasks.clear();
121         isTalking = false;
122         synchronized (this) {
123             notifyAll();
124         }
125     }
126 
127     public void setTalking(boolean isTalking) {
128         this.isTalking = isTalking;
129     }
130 }

结果花费1.6s；

  1 package com.csizg.test;
  2 
  3 
  4 import java.util.ArrayList;
  5 import java.util.List;
  6 
  7 /**
  8  * 与芯片交互线程
  9  */
 10 public class SpiQueue implements Runnable {
 11 
 12     private static final String TAG = SpiQueue.class.getSimpleName();
 13 
 14     private static final byte INIT = 0;// 初始化
 15     private static final byte RUNNING = 1;// 执行中
 16     private static final byte WITING = 2;// 暂停等待中
 17     private static final byte DONE = 3;// 结束
 18 
 19     private byte state = INIT;// 执行状态
 20 
 21     private static SpiQueue spiQueue = null;
 22     private boolean isTalking = false;
 23 
 24     private SpiQueue() {
 25 
 26     }
 27 
 28     public static SpiQueue getSpiQueue() {
 29         if (spiQueue == null) {
 30             spiQueue = new SpiQueue();
 31         }
 32         return spiQueue;
 33     }
 34 
 35     private Thread thread;
 36     private List<SpiTask> tasks = new ArrayList<>();
 37 
 38     @Override
 39     public void run() {
 40         state = RUNNING;
 41         while (state != DONE) {
 42             synchronized (this) {
 43                 SpiTask currentTask = getNextTask();
 44                 if (currentTask == null) {
 45                     if (isTalking) {
 46                         System.out.println(TAG + "  run  " + "no task todo begin to sleep");
 47                         try {
 48                             Thread.sleep(5);
 49                         } catch (InterruptedException e) {
 50                             e.printStackTrace();
 51                         }
 52                         continue;
 53                     } else {
 54                         System.out.println(TAG + "  run  " + "no task todo begin to waiting");
 55                         try {
 56                             state = WITING;
 57                             wait();
 58                         } catch (InterruptedException e) {
 59                             e.printStackTrace();
 60                         }
 61                     }
 62                 } else {
 63                     try {
 64                         Thread.sleep(10);
 65                     } catch (InterruptedException e) {
 66                         e.printStackTrace();
 67                     }
 68                     System.out.println(TAG + "  run  " + "currentTask = " + currentTask.toString());
 69                 }
 70             }
 71         }
 72 
 73     }
 74 
 75     private synchronized SpiTask getNextTask() {
 76         System.out.println(TAG + "  getNextTask  " + "tasks.size() = " + tasks.size());
 77         if (tasks.size() > 0) {
 78             SpiTask task = tasks.remove(0);
 79             return task;
 80         }
 81         return null;
 82     }
 83 
 84     public synchronized void addTask(SpiTask task) {
 85         System.out.println(TAG + "  addTask  " + "tasks.size() = " + tasks.size() + ", new task : " + task.getCode());
 86         if (state == DONE) {
 87             System.out.println(TAG + "  addTask  " + "Thread is DONE : task : " + task.getCode());
 88             return;
 89         }
 90         tasks.add(task);
 91         if (state != RUNNING) {
 92             synchronized (this) {
 93                 state = RUNNING;
 94                 System.out.println(TAG + "  addTask notifyAll ");
 95                 notifyAll();
 96             }
 97         }
 98     }
 99 
100     public synchronized void start() {
101         System.out.println(TAG + "   start   " + "state = " + state);
102         if (state == RUNNING || state == WITING) {
103             return;
104         }
105         state = INIT;
106         // 运行本线程
107         tasks.clear();
108         if (thread != null) {
109             thread.interrupt();
110         }
111         thread = new Thread(this);
112         thread.start();
113     }
114 
115 
116     public synchronized void stop() {
117         state = DONE;
118         tasks.clear();
119         isTalking = false;
120         synchronized (this) {
121             notifyAll();
122         }
123     }
124 
125     public void setTalking(boolean isTalking) {
126         this.isTalking = isTalking;
127     }
128 }

花费时间11.2s；

测试调用代码：

 1 public void test() {
 2         SpiTask spiTask = null;
 3         for (int i = 0; i < 30; i++) {
 4             spiTask = new SpiTask("Thread --- " + i, "" + i);
 5             if (i > 6) {
 6                 SpiQueue.getSpiQueue().setTalking(true);
 7             }
 8             SpiQueue.getSpiQueue().addTask(spiTask);
 9             try {
10                 Thread.sleep(20);
11             } catch (InterruptedException e) {
12                 e.printStackTrace();
13             }
14         }
15         SpiQueue.getSpiQueue().setTalking(false);
16     }

当synchronized同步代码块中去掉Thread.sleep(5)时，结果一致，都是1.6s左右。

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原文地址：https://www.cnblogs.com/zx-blog/p/11851270.html