/** 
    * Parameters: 
     corePoolSize 
       the number of threads to keep in the pool, even if they are idle, unless allowCoreThreadTimeOut is set 
     maximumPoolSize 
       the maximum number of threads to allow in the pool 
     keepAliveTime 
       when the number of threads is greater than the core, this is the maximum time that excess idle threads will wait for new tasks before terminating. 
     unit 
       the time unit for the keepAliveTime argument 
     workQueue 
       the queue to use for holding tasks before they are executed. This queue will hold only the Runnable tasks submitted          by the execute method. 
     handler 
       the handler to use when execution is blocked because the thread bounds and queue capacities are reached 
    Throws: 
     IllegalArgumentException - if one of the following holds: 
     corePoolSize < 0 
     keepAliveTime < 0 
     maximumPoolSize <= 0 
     maximumPoolSize < corePoolSize 
     NullPointerException - if workQueue or handler is null 
    */ 
   ThreadPoolExecutor threadpool=new ThreadPoolExecutor(corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue, handler) 

public class ThreadManager { 
  public static final String DEFAULT_SINGLE_POOL_NAME = "DEFAULT_SINGLE_POOL_NAME"; 
  private static ThreadPoolProxy mLongPool = null; 
  private static Object mLongLock = new Object(); 
  private static ThreadPoolProxy mShortPool = null; 
  private static Object mShortLock = new Object(); 
  private static ThreadPoolProxy mDownloadPool = null; 
  private static Object mDownloadLock = new Object(); 
  private static Map<String, ThreadPoolProxy> mMap = new HashMap<String, ThreadPoolProxy>(); 
  private static Object mSingleLock = new Object(); 
  /** 获取下载线程 */ 
  public static ThreadPoolProxy getDownloadPool() { 
    synchronized (mDownloadLock) { 
      if (mDownloadPool == null) { 
        mDownloadPool = new ThreadPoolProxy(3, 3, 5L); 
      } 
      return mDownloadPool; 
    } 
  } 
  /** 获取一个用于执行长耗时任务的线程池，避免和短耗时任务处在同一个队列而阻塞了重要的短耗时任务，通常用来联网操作 */ 
  public static ThreadPoolProxy getLongPool() { 
    synchronized (mLongLock) { 
      if (mLongPool == null) { 
        mLongPool = new ThreadPoolProxy(5, 5, 5L); 
      } 
      return mLongPool; 
    } 
  } 
  /** 获取一个用于执行短耗时任务的线程池，避免因为和耗时长的任务处在同一个队列而长时间得不到执行，通常用来执行本地的IO/SQL */ 
  public static ThreadPoolProxy getShortPool() { 
    synchronized (mShortLock) { 
      if (mShortPool == null) { 
        mShortPool = new ThreadPoolProxy(2, 2, 5L); 
      } 
      return mShortPool; 
    } 
  } 
  /** 获取一个单线程池，所有任务将会被按照加入的顺序执行，免除了同步开销的问题 */ 
  public static ThreadPoolProxy getSinglePool() { 
    return getSinglePool(DEFAULT_SINGLE_POOL_NAME); 
  } 
  /** 获取一个单线程池，所有任务将会被按照加入的顺序执行，免除了同步开销的问题 */ 
  public static ThreadPoolProxy getSinglePool(String name) { 
    synchronized (mSingleLock) { 
      ThreadPoolProxy singlePool = mMap.get(name); 
      if (singlePool == null) { 
        singlePool = new ThreadPoolProxy(1, 1, 5L); 
        mMap.put(name, singlePool); 
      } 
      return singlePool; 
    } 
  } 
  public static class ThreadPoolProxy { 
    private ThreadPoolExecutor mPool; 
    private int mCorePoolSize; 
    private int mMaximumPoolSize; 
    private long mKeepAliveTime; 
    private ThreadPoolProxy(int corePoolSize, int maximumPoolSize, long keepAliveTime) { 
      mCorePoolSize = corePoolSize; 
      mMaximumPoolSize = maximumPoolSize; 
      mKeepAliveTime = keepAliveTime; 
    } 
    /** 执行任务，当线程池处于关闭，将会重新创建新的线程池 */ 
    public synchronized void execute(Runnable run) { 
      if (run == null) { 
        return; 
      } 
      if (mPool == null || mPool.isShutdown()) { 
        mPool = new ThreadPoolExecutor(mCorePoolSize, mMaximumPoolSize, mKeepAliveTime, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>(), Executors.defaultThreadFactory(), new AbortPolicy()); 
      } 
      mPool.execute(run); 
    } 
    /** 取消线程池中某个还未执行的任务 */ 
    public synchronized void cancel(Runnable run) { 
      if (mPool != null && (!mPool.isShutdown() || mPool.isTerminating())) { 
        mPool.getQueue().remove(run); 
      } 
    } 
    /** 取消线程池中某个还未执行的任务 */ 
    public synchronized boolean contains(Runnable run) { 
      if (mPool != null && (!mPool.isShutdown() || mPool.isTerminating())) { 
        return mPool.getQueue().contains(run); 
      } else { 
        return false; 
      } 
    } 
    /** 立刻关闭线程池，并且正在执行的任务也将会被中断 */ 
    public void stop() { 
      if (mPool != null && (!mPool.isShutdown() || mPool.isTerminating())) { 
        mPool.shutdownNow(); 
      } 
    } 
    /** 平缓关闭单任务线程池，但是会确保所有已经加入的任务都将会被执行完毕才关闭 */ 
    public synchronized void shutdown() { 
      if (mPool != null && (!mPool.isShutdown() || mPool.isTerminating())) { 
        mPool.shutdownNow(); 
      } 
    } 
  } 
} 

/** 下载任务 */ 
 public class DownloadTask implements Runnable { 
   private DownloadInfo info; 
   public DownloadTask(DownloadInfo info) { 
     this.info = info; 
   } 
   @Override 
   public void run() { 
     info.setDownloadState(STATE_DOWNLOADING);// 先改变下载状态 
     notifyDownloadStateChanged(info); 
     File file = new File(info.getPath());// 获取下载文件 
     HttpResult httpResult = null; 
     InputStream stream = null; 
     if (info.getCurrentSize() == 0 || !file.exists() 
         || file.length() != info.getCurrentSize()) { 
       // 如果文件不存在，或者进度为0，或者进度和文件长度不相符，就需要重新下载 
       info.setCurrentSize(0); 
       file.delete(); 
     } 
     httpResult = HttpHelper.download(info.getUrl()); 
     // else { 
     // // //文件存在且长度和进度相等，采用断点下载 
     // httpResult = HttpHelper.download(info.getUrl() + "&range=" + 
     // info.getCurrentSize()); 
     // } 
     if (httpResult == null 
         || (stream = httpResult.getInputStream()) == null) { 
       info.setDownloadState(STATE_ERROR);// 没有下载内容返回，修改为错误状态 
       notifyDownloadStateChanged(info); 
     } else { 
       try { 
         skipBytesFromStream(stream, info.getCurrentSize()); 
       } catch (Exception e1) { 
         e1.printStackTrace(); 
       } 
       FileOutputStream fos = null; 
       try { 
         fos = new FileOutputStream(file, true); 
         int count = -1; 
         byte[] buffer = new byte[1024]; 
         while (((count = stream.read(buffer)) != -1) 
             && info.getDownloadState() == STATE_DOWNLOADING) { 
           // 每次读取到数据后，都需要判断是否为下载状态，如果不是，下载需要终止，如果是，则刷新进度 
           fos.write(buffer, 0, count); 
           fos.flush(); 
           info.setCurrentSize(info.getCurrentSize() + count); 
           notifyDownloadProgressed(info);// 刷新进度 
         } 
       } catch (Exception e) { 
         info.setDownloadState(STATE_ERROR); 
         notifyDownloadStateChanged(info); 
         info.setCurrentSize(0); 
         file.delete(); 
       } finally { 
         IOUtils.close(fos); 
         if (httpResult != null) { 
           httpResult.close(); 
         } 
       } 
       // 判断进度是否和app总长度相等 
       if (info.getCurrentSize() == info.getAppSize()) { 
         info.setDownloadState(STATE_DOWNLOADED); 
         notifyDownloadStateChanged(info); 
       } else if (info.getDownloadState() == STATE_PAUSED) {// 判断状态 
         notifyDownloadStateChanged(info); 
       } else { 
         info.setDownloadState(STATE_ERROR); 
         notifyDownloadStateChanged(info); 
         info.setCurrentSize(0);// 错误状态需要删除文件 
         file.delete(); 
       } 
     } 
     mTaskMap.remove(info.getId()); 
   } 
 } 

fos = new FileOutputStream(file, true); 
     int count = -1; 
     byte[] buffer = new byte[1024]; 
     while (((count = stream.read(buffer)) != -1) 
         && info.getDownloadState() == STATE_DOWNLOADING) { 
       // 每次读取到数据后，都需要判断是否为下载状态，如果不是，下载需要终止，如果是，则刷新进度 
       fos.write(buffer, 0, count); 
       fos.flush(); 
       info.setCurrentSize(info.getCurrentSize() + count); 
       notifyDownloadProgressed(info);// 刷新进度 
     } 

public class RecommendAdapter extends BaseAdapter implements 
    DownloadManager.DownloadObserver { 
  ArrayList<AppInfo> list; 
  private List<ViewHolder> mDisplayedHolders; 
  private FinalBitmap finalBitmap; 
  private Context context; 
  public RecommendAdapter(ArrayList<AppInfo> list, FinalBitmap finalBitmap, 
      Context context) { 
    this.list = list; 
    this.context = context; 
    this.finalBitmap = finalBitmap; 
    mDisplayedHolders = new ArrayList<ViewHolder>(); 
  } 
 
  public void startObserver() { 
    DownloadManager.getInstance().registerObserver(this); 
  } 
  public void stopObserver() { 
    DownloadManager.getInstance().unRegisterObserver(this); 
  } 
  @Override 
  public int getCount() { 
    return list.size(); 
  } 
  @Override 
  public Object getItem(int position) { 
    return list.get(position); 
  } 
  @Override 
  public long getItemId(int position) { 
    return position; 
  } 
  @Override 
  public View getView(int position, View convertView, ViewGroup parent) { 
    final AppInfo appInfo = list.get(position); 
    final ViewHolder holder; 
    if (convertView == null) { 
      holder = new ViewHolder(context); 
    } else { 
      holder = (ViewHolder) convertView.getTag(); 
    } 
    holder.setData(appInfo); 
    mDisplayedHolders.add(holder); 
    return holder.getRootView(); 
  } 
  @Override 
  public void onDownloadStateChanged(DownloadInfo info) { 
    refreshHolder(info); 
  } 
  @Override 
  public void onDownloadProgressed(DownloadInfo info) { 
    refreshHolder(info); 
  } 
  public List<ViewHolder> getDisplayedHolders() { 
    synchronized (mDisplayedHolders) { 
      return new ArrayList<ViewHolder>(mDisplayedHolders); 
    } 
  } 
  public void clearAllItem() { 
    if (list != null){ 
      list.clear(); 
    } 
    if (mDisplayedHolders != null) { 
      mDisplayedHolders.clear(); 
    } 
  } 
  public void addItems(ArrayList<AppInfo> infos) { 
    list.addAll(infos); 
  } 
  private void refreshHolder(final DownloadInfo info) { 
    List<ViewHolder> displayedHolders = getDisplayedHolders(); 
    for (int i = 0; i < displayedHolders.size(); i++) { 
      final ViewHolder holder = displayedHolders.get(i); 
      AppInfo appInfo = holder.getData(); 
      if (appInfo.getId() == info.getId()) { 
        AppUtil.post(new Runnable() { 
          @Override 
          public void run() { 
            holder.refreshState(info.getDownloadState(), 
                info.getProgress()); 
          } 
        }); 
      } 
    } 
  } 
  public class ViewHolder { 
    public TextView textView01; 
    public TextView textView02; 
    public TextView textView03; 
    public TextView textView04; 
    public ImageView imageView_icon; 
    public Button button; 
    public LinearLayout linearLayout; 
    public AppInfo mData; 
    private DownloadManager mDownloadManager; 
    private int mState; 
    private float mProgress; 
    protected View mRootView; 
    private Context context; 
    private boolean hasAttached; 
    public ViewHolder(Context context) { 
      mRootView = initView(); 
      mRootView.setTag(this); 
      this.context = context; 
 
    } 
    public View getRootView() { 
      return mRootView; 
    } 
    public View initView() { 
      View view = AppUtil.inflate(R.layout.item_recommend_award); 
      imageView_icon = (ImageView) view 
          .findViewById(R.id.imageview_task_app_cion); 
      textView01 = (TextView) view 
          .findViewById(R.id.textview_task_app_name); 
      textView02 = (TextView) view 
          .findViewById(R.id.textview_task_app_size); 
      textView03 = (TextView) view 
          .findViewById(R.id.textview_task_app_desc); 
      textView04 = (TextView) view 
          .findViewById(R.id.textview_task_app_love); 
      button = (Button) view.findViewById(R.id.button_task_download); 
      linearLayout = (LinearLayout) view 
          .findViewById(R.id.linearlayout_task); 
      button.setOnClickListener(new OnClickListener() { 
        @Override 
        public void onClick(View v) { 
          System.out.println("mState:173  "+mState); 
          if (mState == DownloadManager.STATE_NONE 
              || mState == DownloadManager.STATE_PAUSED 
              || mState == DownloadManager.STATE_ERROR) { 
            mDownloadManager.download(mData); 
          } else if (mState == DownloadManager.STATE_WAITING 
              || mState == DownloadManager.STATE_DOWNLOADING) { 
            mDownloadManager.pause(mData); 
          } else if (mState == DownloadManager.STATE_DOWNLOADED) { 
//           tell2Server(); 
            mDownloadManager.install(mData); 
          } 
        } 
      }); 
      return view; 
    } 
 
    public void setData(AppInfo data) { 
      if (mDownloadManager == null) { 
        mDownloadManager = DownloadManager.getInstance(); 
      } 
       String filepath= FileUtil.getDownloadDir(AppUtil.getContext()) + File.separator + data.getName() + ".apk"; 
        boolean existsFile = FileUtil.isExistsFile(filepath); 
        if(existsFile){ 
          int fileSize = FileUtil.getFileSize(filepath); 
          if(data.getSize()==fileSize){ 
            DownloadInfo downloadInfo = DownloadInfo.clone(data); 
            downloadInfo.setCurrentSize(data.getSize()); 
            downloadInfo.setHasFinished(true); 
            mDownloadManager.setDownloadInfo(data.getId(),downloadInfo ); 
          } 
//         else if(fileSize>0){ 
//           DownloadInfo downloadInfo = DownloadInfo.clone(data); 
//           downloadInfo.setCurrentSize(data.getSize()); 
//           downloadInfo.setHasFinished(false); 
//           mDownloadManager.setDownloadInfo(data.getId(),downloadInfo ); 
//         } 
        } 
      DownloadInfo downloadInfo = mDownloadManager.getDownloadInfo(data 
          .getId()); 
      if (downloadInfo != null) { 
        mState = downloadInfo.getDownloadState(); 
        mProgress = downloadInfo.getProgress(); 
      } else { 
        mState = DownloadManager.STATE_NONE; 
        mProgress = 0; 
      } 
      this.mData = data; 
      refreshView(); 
    } 
    public AppInfo getData() { 
      return mData; 
    } 
    public void refreshView() { 
      linearLayout.removeAllViews(); 
      AppInfo info = getData(); 
      textView01.setText(info.getName()); 
      textView02.setText(FileUtil.FormetFileSize(info.getSize())); 
      textView03.setText(info.getDes()); 
      textView04.setText(info.getDownloadNum() + "下载量); 
      finalBitmap.display(imageView_icon, info.getIconUrl()); 
 
      if (info.getType().equals("0")) { 
//       mState = DownloadManager.STATE_READ; 
        textView02.setVisibility(View.GONE); 
      }else{ 
        String path=FileUtil.getDownloadDir(AppUtil.getContext()) + File.separator + info.getName() + ".apk"; 
        hasAttached = FileUtil.isValidAttach(path, false); 
        DownloadInfo downloadInfo = mDownloadManager.getDownloadInfo(info 
            .getId()); 
        if (downloadInfo != null && hasAttached) { 
          if(downloadInfo.isHasFinished()){ 
            mState = DownloadManager.STATE_DOWNLOADED; 
          }else{ 
            mState = DownloadManager.STATE_PAUSED; 
          } 
        } else { 
          mState = DownloadManager.STATE_NONE; 
          if(downloadInfo !=null){ 
            downloadInfo.setDownloadState(mState); 
          } 
        } 
      } 
      refreshState(mState, mProgress); 
    } 
    public void refreshState(int state, float progress) { 
      mState = state; 
      mProgress = progress; 
      switch (mState) { 
      case DownloadManager.STATE_NONE: 
        button.setText(R.string.app_state_download); 
        break; 
      case DownloadManager.STATE_PAUSED: 
        button.setText(R.string.app_state_paused); 
        break; 
      case DownloadManager.STATE_ERROR: 
        button.setText(R.string.app_state_error); 
        break; 
      case DownloadManager.STATE_WAITING: 
        button.setText(R.string.app_state_waiting); 
        break; 
      case DownloadManager.STATE_DOWNLOADING: 
        button.setText((int) (mProgress * 100) + "%"); 
        break; 
      case DownloadManager.STATE_DOWNLOADED: 
        button.setText(R.string.app_state_downloaded); 
        break; 
//     case DownloadManager.STATE_READ: 
//       button.setText(R.string.app_state_read); 
//       break; 
      default: 
        break; 
      } 
    } 
  } 
} 

public void startObserver() { 
    DownloadManager.getInstance().registerObserver(this); 
  } 

public interface DownloadObserver { 
  public void onDownloadStateChanged(DownloadInfo info); 
  public void onDownloadProgressed(DownloadInfo info); 
} 

@Override 
 public void onDownloadStateChanged(DownloadInfo info) { 
   refreshHolder(info); 
 } 
 @Override 
 public void onDownloadProgressed(DownloadInfo info) { 
   refreshHolder(info); 
 } 

** 当下载状态发送改变的时候回调 */ 
public void notifyDownloadStateChanged(DownloadInfo info) { 
  synchronized (mObservers) { 
    for (DownloadObserver observer : mObservers) { 
      observer.onDownloadStateChanged(info); 
    } 
  } 
} 
/** 当下载进度发送改变的时候回调 */ 
public void notifyDownloadProgressed(DownloadInfo info) { 
  synchronized (mObservers) { 
    for (DownloadObserver observer : mObservers) { 
      observer.onDownloadProgressed(info); 
    } 
  } 
} 

/* 注册观察者 /  
public void registerObserver(DownloadObserver observer) {  
synchronized (mObservers) {  
if (!mObservers.contains(observer)) {  
mObservers.add(observer);  
}  
}  
} 
[java] view plaincopy
/** 反注册观察者 */ 
public void unRegisterObserver(DownloadObserver observer) { 
  synchronized (mObservers) { 
    if (mObservers.contains(observer)) { 
      mObservers.remove(observer); 
    } 
  } 
} 

public class DownloadManager { 
  public static final int STATE_NONE = 0; 
  /** 等待中 */ 
  public static final int STATE_WAITING = 1; 
  /** 下载中 */ 
  public static final int STATE_DOWNLOADING = 2; 
  /** 暂停 */ 
  public static final int STATE_PAUSED = 3; 
  /** 下载完毕 */ 
  public static final int STATE_DOWNLOADED = 4; 
  /** 下载失败 */ 
  public static final int STATE_ERROR = 5; 
  // public static final int STATE_READ = 6; 
  private static DownloadManager instance; 
  private DownloadManager() { 
  } 
  /** 用于记录下载信息，如果是正式项目，需要持久化保存 */ 
  private Map<Long, DownloadInfo> mDownloadMap = new ConcurrentHashMap<Long, DownloadInfo>(); 
  /** 用于记录观察者，当信息发送了改变，需要通知他们 */ 
  private List<DownloadObserver> mObservers = new ArrayList<DownloadObserver>(); 
  /** 用于记录所有下载的任务，方便在取消下载时，通过id能找到该任务进行删除 */ 
  private Map<Long, DownloadTask> mTaskMap = new ConcurrentHashMap<Long, DownloadTask>(); 
  public static synchronized DownloadManager getInstance() { 
    if (instance == null) { 
      instance = new DownloadManager(); 
    } 
    return instance; 
  } 
  /** 注册观察者 */ 
  public void registerObserver(DownloadObserver observer) { 
    synchronized (mObservers) { 
      if (!mObservers.contains(observer)) { 
        mObservers.add(observer); 
      } 
    } 
  } 
  /** 反注册观察者 */ 
  public void unRegisterObserver(DownloadObserver observer) { 
    synchronized (mObservers) { 
      if (mObservers.contains(observer)) { 
        mObservers.remove(observer); 
      } 
    } 
  } 
  /** 当下载状态发送改变的时候回调 */ 
  public void notifyDownloadStateChanged(DownloadInfo info) { 
    synchronized (mObservers) { 
      for (DownloadObserver observer : mObservers) { 
        observer.onDownloadStateChanged(info); 
      } 
    } 
  } 
  /** 当下载进度发送改变的时候回调 */ 
  public void notifyDownloadProgressed(DownloadInfo info) { 
    synchronized (mObservers) { 
      for (DownloadObserver observer : mObservers) { 
        observer.onDownloadProgressed(info); 
      } 
    } 
  } 
  /** 下载，需要传入一个appInfo对象 */ 
  public synchronized void download(AppInfo appInfo) { 
    // 先判断是否有这个app的下载信息 
    DownloadInfo info = mDownloadMap.get(appInfo.getId()); 
    if (info == null) {// 如果没有，则根据appInfo创建一个新的下载信息 
      info = DownloadInfo.clone(appInfo); 
      mDownloadMap.put(appInfo.getId(), info); 
    } 
    // 判断状态是否为STATE_NONE、STATE_PAUSED、STATE_ERROR。只有这3种状态才能进行下载，其他状态不予处理 
    if (info.getDownloadState() == STATE_NONE 
        || info.getDownloadState() == STATE_PAUSED 
        || info.getDownloadState() == STATE_ERROR) { 
      // 下载之前，把状态设置为STATE_WAITING，因为此时并没有产开始下载，只是把任务放入了线程池中，当任务真正开始执行时，才会改为STATE_DOWNLOADING 
      info.setDownloadState(STATE_WAITING); 
      notifyDownloadStateChanged(info);// 每次状态发生改变，都需要回调该方法通知所有观察者 
      DownloadTask task = new DownloadTask(info);// 创建一个下载任务，放入线程池 
      mTaskMap.put(info.getId(), task); 
      ThreadManager.getDownloadPool().execute(task); 
    } 
  } 
  /** 暂停下载 */ 
  public synchronized void pause(AppInfo appInfo) { 
    stopDownload(appInfo); 
    DownloadInfo info = mDownloadMap.get(appInfo.getId());// 找出下载信息 
    if (info != null) {// 修改下载状态 
      info.setDownloadState(STATE_PAUSED); 
      notifyDownloadStateChanged(info); 
    } 
  } 
  /** 取消下载，逻辑和暂停类似，只是需要删除已下载的文件 */ 
  public synchronized void cancel(AppInfo appInfo) { 
    stopDownload(appInfo); 
    DownloadInfo info = mDownloadMap.get(appInfo.getId());// 找出下载信息 
    if (info != null) {// 修改下载状态并删除文件 
      info.setDownloadState(STATE_NONE); 
      notifyDownloadStateChanged(info); 
      info.setCurrentSize(0); 
      File file = new File(info.getPath()); 
      file.delete(); 
    } 
  } 
  /** 安装应用 */ 
  public synchronized void install(AppInfo appInfo) { 
    stopDownload(appInfo); 
    DownloadInfo info = mDownloadMap.get(appInfo.getId());// 找出下载信息 
    if (info != null) {// 发送安装的意图 
      Intent installIntent = new Intent(Intent.ACTION_VIEW); 
      installIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
      installIntent.setDataAndType(Uri.parse("file://" + info.getPath()), 
          "application/vnd.android.package-archive"); 
      AppUtil.getContext().startActivity(installIntent); 
    } 
    notifyDownloadStateChanged(info); 
  } 
  /** 启动应用，启动应用是最后一个 */ 
  public synchronized void open(AppInfo appInfo) { 
    try { 
      Context context = AppUtil.getContext(); 
      // 获取启动Intent 
      Intent intent = context.getPackageManager() 
          .getLaunchIntentForPackage(appInfo.getPackageName()); 
      context.startActivity(intent); 
    } catch (Exception e) { 
    } 
  } 
  /** 如果该下载任务还处于线程池中，且没有执行，先从线程池中移除 */ 
  private void stopDownload(AppInfo appInfo) { 
    DownloadTask task = mTaskMap.remove(appInfo.getId());// 先从集合中找出下载任务 
    if (task != null) { 
      ThreadManager.getDownloadPool().cancel(task);// 然后从线程池中移除 
    } 
  } 
  /** 获取下载信息 */ 
  public synchronized DownloadInfo getDownloadInfo(long id) { 
    return mDownloadMap.get(id); 
  } 
  public synchronized void setDownloadInfo(long id, DownloadInfo info) { 
    mDownloadMap.put(id, info); 
  } 
  /** 下载任务 */ 
  public class DownloadTask implements Runnable { 
    private DownloadInfo info; 
    public DownloadTask(DownloadInfo info) { 
      this.info = info; 
    } 
    @Override 
    public void run() { 
      info.setDownloadState(STATE_DOWNLOADING);// 先改变下载状态 
      notifyDownloadStateChanged(info); 
      File file = new File(info.getPath());// 获取下载文件 
      HttpResult httpResult = null; 
      InputStream stream = null; 
      if (info.getCurrentSize() == 0 || !file.exists() 
          || file.length() != info.getCurrentSize()) { 
        // 如果文件不存在，或者进度为0，或者进度和文件长度不相符，就需要重新下载 
        info.setCurrentSize(0); 
        file.delete(); 
      } 
      httpResult = HttpHelper.download(info.getUrl()); 
      // else { 
      // // //文件存在且长度和进度相等，采用断点下载 
      // httpResult = HttpHelper.download(info.getUrl() + "&range=" + 
      // info.getCurrentSize()); 
      // } 
      if (httpResult == null 
          || (stream = httpResult.getInputStream()) == null) { 
        info.setDownloadState(STATE_ERROR);// 没有下载内容返回，修改为错误状态 
        notifyDownloadStateChanged(info); 
      } else { 
        try { 
          skipBytesFromStream(stream, info.getCurrentSize()); 
        } catch (Exception e1) { 
          e1.printStackTrace(); 
        } 
        FileOutputStream fos = null; 
        try { 
          fos = new FileOutputStream(file, true); 
          int count = -1; 
          byte[] buffer = new byte[1024]; 
          while (((count = stream.read(buffer)) != -1) 
              && info.getDownloadState() == STATE_DOWNLOADING) { 
            // 每次读取到数据后，都需要判断是否为下载状态，如果不是，下载需要终止，如果是，则刷新进度 
            fos.write(buffer, 0, count); 
            fos.flush(); 
            info.setCurrentSize(info.getCurrentSize() + count); 
            notifyDownloadProgressed(info);// 刷新进度 
          } 
        } catch (Exception e) { 
          info.setDownloadState(STATE_ERROR); 
          notifyDownloadStateChanged(info); 
          info.setCurrentSize(0); 
          file.delete(); 
        } finally { 
          IOUtils.close(fos); 
          if (httpResult != null) { 
            httpResult.close(); 
          } 
        } 
        // 判断进度是否和app总长度相等 
        if (info.getCurrentSize() == info.getAppSize()) { 
          info.setDownloadState(STATE_DOWNLOADED); 
          notifyDownloadStateChanged(info); 
        } else if (info.getDownloadState() == STATE_PAUSED) {// 判断状态 
          notifyDownloadStateChanged(info); 
        } else { 
          info.setDownloadState(STATE_ERROR); 
          notifyDownloadStateChanged(info); 
          info.setCurrentSize(0);// 错误状态需要删除文件 
          file.delete(); 
        } 
      } 
      mTaskMap.remove(info.getId()); 
    } 
  } 
  public interface DownloadObserver { 
    public abstract void onDownloadStateChanged(DownloadInfo info); 
    public abstract void onDownloadProgressed(DownloadInfo info); 
  } 
  /* 重写了Inpustream 中的skip(long n) 方法，将数据流中起始的n 个字节跳过 */ 
  private long skipBytesFromStream(InputStream inputStream, long n) { 
    long remaining = n; 
    // SKIP_BUFFER_SIZE is used to determine the size of skipBuffer 
    int SKIP_BUFFER_SIZE = 10000; 
    // skipBuffer is initialized in skip(long), if needed. 
    byte[] skipBuffer = null; 
    int nr = 0; 
    if (skipBuffer == null) { 
      skipBuffer = new byte[SKIP_BUFFER_SIZE]; 
    } 
    byte[] localSkipBuffer = skipBuffer; 
    if (n <= 0) { 
      return 0; 
    } 
    while (remaining > 0) { 
      try { 
        long skip = inputStream.skip(10000); 
        nr = inputStream.read(localSkipBuffer, 0, 
            (int) Math.min(SKIP_BUFFER_SIZE, remaining)); 
      } catch (IOException e) { 
        e.printStackTrace(); 
      } 
      if (nr < 0) { 
        break; 
      } 
      remaining -= nr; 
    } 
    return n - remaining; 
  } 
} 

// //文件存在且长度和进度相等，采用断点下载 
      httpResult = HttpHelper.download(info.getUrl() + "&range=" + info.getCurrentSize()); 

FileInputStream stream = new FileInputStream(file); 
     int count = -1; 
     byte[] buffer = new byte[1024]; 
     while ((count = stream.read(buffer)) != -1) { 
       SystemClock.sleep(20); 
       out.write(buffer, 0, count); 
       out.flush(); 
     } 
     stream.close(); 
     out.close(); 

RandomAccessFile raf = new RandomAccessFile(file, "r"); 
      raf.seek(Long.valueOf(range));  
      int count = -1; 
      byte[] buffer = new byte[1024]; 
      while ((count = raf.read(buffer)) != -1) { 
        SystemClock.sleep(10); 
        out.write(buffer, 0, count); 
        out.flush(); 
      } 
      raf.close(); 
      out.close(); 

@Override 
    public void run() { 
      info.setDownloadState(STATE_DOWNLOADING);// 先改变下载状态 
      notifyDownloadStateChanged(info); 
      File file = new File(info.getPath());// 获取下载文件 
      HttpResult httpResult = null; 
      InputStream stream = null; 
      if (info.getCurrentSize() == 0 || !file.exists() 
          || file.length() != info.getCurrentSize()) { 
        // 如果文件不存在，或者进度为0，或者进度和文件长度不相符，就需要重新下载 
<span>        </span>info.setCurrentSize(0); 
        file.delete(); 
      } 
      httpResult = HttpHelper.download(info.getUrl()); 
      if (httpResult == null 
          || (stream = httpResult.getInputStream()) == null) { 
        info.setDownloadState(STATE_ERROR);// 没有下载内容返回，修改为错误状态 
        notifyDownloadStateChanged(info); 
      } else { 
        try { 
          skipBytesFromStream(stream, info.getCurrentSize()); 
        } catch (Exception e1) { 
          e1.printStackTrace(); 
        } 
        FileOutputStream fos = null; 
        try { 
          fos = new FileOutputStream(file, true); 
          int count = -1; 
          byte[] buffer = new byte[1024]; 
          while (((count = stream.read(buffer)) != -1) 
              && info.getDownloadState() == STATE_DOWNLOADING) { 
            // 每次读取到数据后，都需要判断是否为下载状态，如果不是，下载需要终止，如果是，则刷新进度 
            fos.write(buffer, 0, count); 
            fos.flush(); 
            info.setCurrentSize(info.getCurrentSize() + count); 
            notifyDownloadProgressed(info);// 刷新进度 
          } 
        } catch (Exception e) { 
          info.setDownloadState(STATE_ERROR); 
          notifyDownloadStateChanged(info); 
          info.setCurrentSize(0); 
          file.delete(); 
        } finally { 
          IOUtils.close(fos); 
          if (httpResult != null) { 
            httpResult.close(); 
          } 
        } 
<span>        </span>// 判断进度是否和app总长度相等 
        if (info.getCurrentSize() == info.getAppSize()) { 
          info.setDownloadState(STATE_DOWNLOADED); 
          notifyDownloadStateChanged(info); 
        } else if (info.getDownloadState() == STATE_PAUSED) {// 判断状态 
          notifyDownloadStateChanged(info); 
        } else { 
          info.setDownloadState(STATE_ERROR); 
          notifyDownloadStateChanged(info); 
          info.setCurrentSize(0);// 错误状态需要删除文件 
          file.delete(); 
        } 
      } 
      mTaskMap.remove(info.getId()); 
    } 

HttpResponse response = httpClient.execute(requestBase, httpContext);//访问网络 

@Override 
    public void run() { 
      info.setDownloadState(STATE_DOWNLOADING);// 先改变下载状态 
      notifyDownloadStateChanged(info); 
      File file = new File(info.getPath());// 获取下载文件 
      /**********************************************************/ 
//     try { 
        try { 
          URL url = new URL(info.getUrl()); 
          HttpURLConnection conn = (HttpURLConnection) url.openConnection(); 
          conn.setRequestMethod("GET"); 
          conn.setConnectTimeout(30000); 
          conn.setReadTimeout(30000); 
          if (!file.exists()) { 
            info.setCurrentSize(0); 
            file.delete(); 
          } else if (file.length() > info.getAppSize()) { 
            info.setCurrentSize(0); 
            file.delete(); 
          } else if (file.length() == info.getAppSize()) { 
          } else if (file.length() < info.getAppSize()) { 
            info.setCurrentSize(file.length()); 
          } 
          if (info.getCurrentSize() == 0 || !file.exists() || file.length() != info.getCurrentSize()) { 
            // 如果文件不存在，或者进度为0，或者进度和文件长度不相符，就需要重新下载 
            info.setCurrentSize(0); 
            file.delete(); 
          } else if (file.length() == info.getCurrentSize() && file.length() < info.getAppSize()) { 
            conn.setRequestProperty("Range", "bytes=" + info.getCurrentSize() + "-" + info.getAppSize()); 
          } 
          int code = conn.getResponseCode(); 
          RandomAccessFile raf = new RandomAccessFile(file, "rw"); 
          InputStream is = conn.getInputStream(); 
          byte[] buffer = new byte[1024 * 8]; 
          int len = -1; 
          int total = 0;// 当前线程下载的总的数据的长度 
          if (code == 200) { 
          } else if (code == 206) { 
            raf.seek(file.length()); 
          } 
          while (((len = is.read(buffer)) != -1) && (info.getDownloadState() == STATE_DOWNLOADING)) { // 下载数据的过程。 
            raf.write(buffer, 0, len); 
            total += len;// 需要记录当前的数据。 
            info.setCurrentSize(info.getCurrentSize() + len); 
            notifyDownloadProgressed(info);// 刷新进度 
          } 
          is.close(); 
          raf.close(); 
        } catch (MalformedURLException e) { 
          // TODO Auto-generated catch block 
          e.printStackTrace(); 
        } catch (ProtocolException e) { 
          // TODO Auto-generated catch block 
          e.printStackTrace(); 
        } catch (FileNotFoundException e) { 
          // TODO Auto-generated catch block 
          e.printStackTrace(); 
        } catch (IOException e) { 
          // TODO Auto-generated catch block 
          e.printStackTrace(); 
        } 
        /*************************对于各种情况，需要删除下载任务，从新下载的 请自己改动代码*****************************/ 
        // 判断进度是否和app总长度相等 
//     } catch (Exception e) { 
//       System.out.println(e.toString()); 
//       info.setDownloadState(STATE_ERROR); 
//       info.setCurrentSize(0); 
//       file.delete(); 
//       e.printStackTrace(); 
//     } 
      if (info.getCurrentSize() == info.getAppSize()) { 
        info.setDownloadState(STATE_DOWNLOADED); 
        notifyDownloadStateChanged(info); 
      } else if (info.getDownloadState() == STATE_PAUSED) {// 判断状态 
        notifyDownloadStateChanged(info); 
      } else { 
        info.setDownloadState(STATE_ERROR); 
        notifyDownloadStateChanged(info); 
        info.setCurrentSize(0);// 错误状态需要删除文件 
        file.delete(); 
      } 
      /**********************************************************/ 
      mTaskMap.remove(info.getId()); 
    } 

if (info.getCurrentSize() == 0 || !file.exists() || file.length() != info.getCurrentSize()) { 
  // 如果文件不存在，或者进度为0，或者进度和文件长度不相符，就需要重新下载 
  info.setCurrentSize(0); 
  file.delete(); 
  } else if (file.length() == info.getCurrentSize() && file.length() < info.getAppSize()) { 
     conn.setRequestProperty("Range", "bytes=" + info.getCurrentSize() + "-" + info.getAppSize()); 
   } 

RandomAccessFile raf = new RandomAccessFile(file, "rw"); 
InputStream is = conn.getInputStream(); 
byte[] buffer = new byte[1024 * 8]; 
int len = -1; 
int total = 0;// 当前线程下载的总的数据的长度 
if (code == 200) { 
} else if (code == 206) { 
raf.seek(file.length()); 
} 

while (((len = is.read(buffer)) != -1) && (info.getDownloadState() == STATE_DOWNLOADING)) { // 下载数据的过程。 
raf.write(buffer, 0, len); 
total += len;// 需要记录当前的数据。 
info.setCurrentSize(info.getCurrentSize() + len); 
notifyDownloadProgressed(info);// 刷新进度 
} 
is.close(); 
raf.close();