Parse开源了一个面向iOS和Android的底层库集合，统称为Bolts。根据Parse的公告，Bolts是Parse和Facebook共同努力将两家公司各自独立开发的小型底层工具类合并的结果。Bolts-Android为一个级联的异步任务。

Bolts-Android github地址：
https://github.com/BoltsFramework/Bolts-Android

本文案例的 github地址：
https://github.com/AndroidHighQualityCodeStudy/Android_Task_ThirdCode_Bolts

使用方式

//###############################第1部分###########################
//运行在后台线程中(与“更新UI相关的网络请求”和“与UI相关的DB请求”用该线程池 )
// 我还定义了一个日志上传线程池，所有的日志上传应该使用LOG_UPLOAD_EXECUTOR线程池，谢谢
public Task<Boolean> runOnBackgroundThread() {
   //
   return Task.call(new Callable<Boolean>() {
       @Override
       public Boolean call() throws Exception {
           // Background_Thread
           return true;
       }
   }, Task.BACKGROUND_EXECUTOR);
}

//运行在当前线程中
public Task<Boolean> runOnCurrentThread() {
   //
   return Task.call(new Callable<Boolean>() {
       @Override
       public Boolean call() throws Exception {
           // Current_Thread
           return true;
       }
   });
}

//运行在UI线程中
public Task<Boolean> runOnUIThread() {
   //
   return Task.call(new Callable<Boolean>() {
       @Override
       public Boolean call() throws Exception {
           // UI_Thread
           return true;
       }
   }, Task.UI_THREAD_EXECUTOR);
}

//###############################第2部分###########################
//任务顺序执行
public Task synchronousTask(CancellationToken cancellationToken) {
   return Task.call(new Callable<Void>() {
       @Override
       public Void call() throws Exception {
           // UI_Thread
           LogUtils.d(TAG, "---1 UI_Thread---");
           return null;
       }
   }, Task.UI_THREAD_EXECUTOR, cancellationToken).onSuccess(new Continuation<Void, Boolean>() {
       @Override
       public Boolean then(Task<Void> task) throws Exception {
           // Background_Thread
           LogUtils.d(TAG, "---2 Background_Thread---");
           return true;
       }
   }, Task.BACKGROUND_EXECUTOR).continueWith(new Continuation<Boolean, Void>() {
       @Override
       public Void then(Task<Boolean> task) throws Exception {
           // UI_Thread
           LogUtils.d(TAG, "---3 UI_Thread---");
           return null;
       }
   }, Task.UI_THREAD_EXECUTOR);
}

//###############################第3部分###########################
//多任务并行
public void whenAll() {
   ArrayList<Task<Void>> tasks = new ArrayList<Task<Void>>();
   for (int i = 0; i < 3; i++) {
       final int index = i;
       // Start this delete immediately and add its task to the list.
       tasks.add(Task.call(new Callable<Void>() {
           @Override
           public Void call() throws Exception {
               // UI_Thread
               LogUtils.d(TAG, "---###########################---");
               LogUtils.d(TAG, "index: " + index);
               return null;
           }
       }, Task.BACKGROUND_EXECUTOR));
   }

   Task.whenAll(tasks);
}

//###############################第4部分###########################
//自定义线程池
static final Executor NETWORK_EXECUTOR = Executors.newCachedThreadPool();
static final Executor DISK_EXECUTOR = Executors.newCachedThreadPool();

//
public void changeThreadPool() {
   Task.call(new Callable<Boolean>() {
       @Override
       public Boolean call() throws Exception {
           // NETWORK_Thread
           return null;
       }
   }, NETWORK_EXECUTOR).continueWith(new Continuation<Boolean, String>() {
       @Override
       public String then(Task<Boolean> task) throws Exception {
           // NETWORK_Thread
           return null;
       }
   }).continueWith(new Continuation<String, Integer>() {
       @Override
       public Integer then(Task<String> task) throws Exception {
           // DISK_Thread
           return null;
       }
   }, DISK_EXECUTOR);
}

//###############################第5部分###########################
//取消任务
public void cancelTask() {
   CancellationTokenSource cts = new CancellationTokenSource();
   Task<Boolean> stringTask = runOnBackgroundThread(cts.getToken());
   cts.cancel();
}

//运行在后台线程中
public Task<Boolean> runOnBackgroundThread(CancellationToken cancellationToken) {
   //
   return Task.call(new Callable<Boolean>() {
       @Override
       public Boolean call() throws Exception {
           // Background_Thread
           return true;
       }
   }, Task.BACKGROUND_EXECUTOR, cancellationToken);
}

= THE END =

文章首发于公众号”CODING技术小馆“，如果文章对您有帮助，欢迎关注我的公众号。
文章首发于公众号”CODING技术小馆“，如果文章对您有帮助，欢迎关注我的公众号。
文章首发于公众号”CODING技术小馆“，如果文章对您有帮助，欢迎关注我的公众号。