Android网络开发 请求队列

文章出处：Android那些事儿的博客

因为之前参与的网络开发项目都遇到一些相同的问题：
1.大量的并发请求造成堵塞，特别是遇上让人无语的3G网络，无限loading。。。
2.一般来说一个网络请求都会用使用到一个异步线程，大量的线程创建、运行、销毁又造成了系统资源的浪费
3.请求结束得到结果后，如果需要更新UI，一个不小心忘了返回UI线程，各种崩溃。。。

前些日子跟同事商量能不能做个请求队列去进行控制，于是趁着热度没消退说干就干，建了个模型，以备日后使用。

在这个模型中，有高中低三个优先级信道如下：高优先级–1，中优先级–3，低优先级–2
规则：
1.正常情况下各个优先级使用各自信道（线程）
2.高级信道满载、中、低级信道空置，则高级请求可使用低级信道

构思：
UI线程将期望的网络请求url和参数通过一个封装好的Runnable提交给Service处理（当然也可以交给一个Thread处理，本例使用Service），Service接收到请求，判断优先级，加入到相应线程池中排队。线程池启动线程发起网络请求，最后通过监听器将结果返回给Service，Service发送广播通知UI线程，UI线程更新相关界面，结束。

废话说完，上例子：
首先是封装好的Runnable

public class HttpConnRunnable implements Runnable, Parcelable {

public static final int HIGH_LEVEL = 0; public static final int NORMAL_LEVEL = 1; public static final int LOW_LEVEL = 2; private int mPriority = NORMAL_LEVEL;//优先级，默认为普通 private String mUrl = ""; private HttpConnListener mListener;//监听器 public HttpConnRunnable() {     super(); } public HttpConnRunnable(int priority) {     super();     mPriority = priority; }    @Override public void run() {     Log.i(Thread.currentThread().getName(), "----Start to connect:" + mUrl + ", priority:" + mPriority + "-----");     try {         Thread.sleep(10000);         //TODO:进行网络请求相关操作，并通过listener返回结果         mListener.onSucceed("Connected to " + mUrl + " succeed!");     }     catch (InterruptedException e) {         e.printStackTrace();     }     Log.i(Thread.currentThread().getName(), "----Finish to connect:" + mUrl + ", priority:" + mPriority + "-----"); } public int getPriority() {     return mPriority; } public void setPriority(int priority) {     mPriority = priority; } public String getURL() {     return mUrl; } public void setURL(String url) {     mUrl = url; } public void setHttpConnListener(HttpConnListener listener) {     mListener = listener; } //序列化，为了传递给Service，如果是使用Thread处理本例，则无需序列化 public static final Parcelable.Creator<HttpConnRunnable> CREATOR = new Creator<HttpConnRunnable>() {     @Override     public HttpConnRunnable createFromParcel(Parcel source) {         HttpConnRunnable data = null;         Bundle bundle = source.readBundle();         if(bundle != null) {             data = new HttpConnRunnable(bundle.getInt("PRIORITY"));             data.mUrl = bundle.getString("URL");         }         return data;     }     @Override     public HttpConnRunnable[] newArray(int size) {         return new HttpConnRunnable[size];     } }; @Override public int describeContents() {     return 0; } @Override public void writeToParcel(Parcel dest, int flags) {     Bundle bundle = new Bundle();     bundle.putInt("PRIORITY", mPriority);     bundle.putString("URL", mUrl);     dest.writeBundle(bundle); } 

}

Service的处理:

public class HttpConnService extends Service implements HttpConnListener {
public static final String HTTP_POOL_PARAM_KEYWORD = “HttpPoolParam”; //网络参数传递的关键字

private final int HIGH_POOL_SIZE = 1; private final int NORMAL_POOL_SIZE = 3; private final int LOW_POOL_SIZE = 2; // 可重用固定线程数的线程池 private ThreadPoolExecutor mHighPool; private ThreadPoolExecutor mNormalPool; private ThreadPoolExecutor mLowPool; @Override public void onCreate() {     //初始化所有     mHighPool = (ThreadPoolExecutor) Executors.newFixedThreadPool(HIGH_POOL_SIZE);     mNormalPool = (ThreadPoolExecutor) Executors.newFixedThreadPool(NORMAL_POOL_SIZE);     mLowPool = (ThreadPoolExecutor) Executors.newFixedThreadPool(LOW_POOL_SIZE);     super.onCreate(); } @Override public int onStartCommand(Intent intent, int flags, int startId) {     //接受到来自UI线程的请求     //取出Runnable，并加入到相应队列     Bundle bundle = intent.getExtras();     HttpConnRunnable httpConnRunnable = bundle.getParcelable(HTTP_POOL_PARAM_KEYWORD);     if (httpConnRunnable != null) {         httpConnRunnable.setHttpConnListener(HttpConnService.this);         int level = httpConnRunnable.getPriority();         switch (level) {             case HttpConnRunnable.HIGH_LEVEL:                 //如果高级池满而低级池未满交由低级池处理                 //如果高级池满而普通池未满交由普通池处理                 //如果高级池未满则交给高级池处理，否则，交由高级池排队等候                 if (mHighPool.getActiveCount() == HIGH_POOL_SIZE && mLowPool.getActiveCount() < LOW_POOL_SIZE) {                     mLowPool.execute(httpConnRunnable);                 }                 else if (mHighPool.getActiveCount() == HIGH_POOL_SIZE && mNormalPool.getActiveCount() < NORMAL_POOL_SIZE) {                     mNormalPool.execute(httpConnRunnable);                 }                 else {                     mHighPool.execute(httpConnRunnable);                 }                 break;             case HttpConnRunnable.NORMAL_LEVEL:                 //如果普通池满而低级池未满交由低级池处理                 //如果普通池未满则交给普通池处理，否则，交由普通池排队等候                 if (mNormalPool.getActiveCount() == NORMAL_POOL_SIZE && mLowPool.getActiveCount() < LOW_POOL_SIZE) {                     mLowPool.execute(httpConnRunnable);                 }                 else {                     mNormalPool.execute(httpConnRunnable);                 }                 break;             case HttpConnRunnable.LOW_LEVEL:                 mLowPool.execute(httpConnRunnable);                 break;         }     }     return super.onStartCommand(intent, flags, startId); } @Override public void onDestroy() {     mHighPool.shutdownNow();     mNormalPool.shutdownNow();     mLowPool.shutdownNow();     mNormalPool = null;     mLowPool = null;     super.onDestroy(); } @Override public IBinder onBind(Intent intent) {     return null; } @Override public void onSucceed(String result) {     Intent intent = new Intent();     intent.setAction("com.ezstudio.connpool.HttpConnReceiver");     // 要发送的内容     intent.putExtra("RESULT", result);     // 发送 一个无序广播     sendBroadcast(intent); } @Override public void onFailed() {     // TODO Auto-generated method stub } 

}

Receiver的处理比较简单：

public class HttpConnReceiver extends BroadcastReceiver {
private HttpConnListener mListener;

public void setHttpConnListener (HttpConnListener listener) {     mListener = listener; } @Override public void onReceive(Context context, Intent intent) {     String action = intent.getAction();     if (action.equals("com.ezstudio.connpool.HttpConnReceiver")) {         String result = intent.getStringExtra("RESULT");         mListener.onSucceed(result);     } } 

}

可能很多同学都看过这么文章，不过由于没有源码可能还是云里雾里，由于我也是个小菜鸟的关系就本着学习的心态对照原博客，可新浪微博发送微博的效果自己实现了队列请求的效果，便记录下来，以便日后拿来用。也将源码分享给大家

源码

此源码是as工程，不会在eclipse导入as工程的同学可以new eclipse工程，拷一下代码和布局文件。。。

菜鸟转载，不喜勿喷