产生java.io.IOException：下载Android中Java的图像文件时

Question

我得到了兴田在这行代码下面的错误

05-10 11:14:47.925: W/System.err(9681): java.io.IOException: BufferedInputStream is closed 
05-10 11:14:47.925: W/System.err(9681):  at java.io.BufferedInputStream.streamClosed(BufferedInputStream.java:118) 
05-10 11:14:47.925: W/System.err(9681):  at java.io.BufferedInputStream.available(BufferedInputStream.java:112) 
05-10 11:14:47.925: W/System.err(9681):  at android.graphics.BitmapFactory.nativeDecodeStream(Native Method) 
05-10 11:14:47.925: W/System.err(9681):  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:529) 
05-10 11:14:47.925: W/System.err(9681):  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:601) 
05-10 11:14:47.925: W/System.err(9681):  at com.laroche.NewsMedia.getImageBitmap(NewsMedia.java:132) 
05-10 11:14:47.932: W/System.err(9681):  at com.laroche.News.getNewsListByCategoryId(News.java:113) 
05-10 11:14:47.932: W/System.err(9681):  at com.laroche.MainActivity$GetDataTask.doInBackground(MainActivity.java:112) 
05-10 11:14:47.932: W/System.err(9681):  at com.laroche.MainActivity$GetDataTask.doInBackground(MainActivity.java:1) 
05-10 11:14:47.932: W/System.err(9681):  at android.os.AsyncTask$2.call(AsyncTask.java:287) 
05-10 11:14:47.932: W/System.err(9681):  at java.util.concurrent.FutureTask.run(FutureTask.java:234) 
05-10 11:14:47.932: W/System.err(9681):  at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230) 
05-10 11:14:47.932: W/System.err(9681):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080) 
05-10 11:14:47.932: W/System.err(9681):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573) 
05-10 11:14:47.932: W/System.err(9681):  at java.lang.Thread.run(Thread.java:856) 

的BufferedInputStream关闭：

BufferedInputStream bufferedInputStream = null; 
    Bitmap bmp = null; 
    String urlString = "http://ma2too3a.com:8084/NewsImages/"+imageName; 
    try { 
     bufferedInputStream = new BufferedInputStream(ws.OpenHttpConnection(urlString)); 
     bmp = BitmapFactory.decodeStream(bufferedInputStream); 

     saveImage(bmp,imageName,c); 
     bufferedInputStream.close(); 


    } catch (IOException e) { 
     // TODO Auto-generated catch block 
     e.printStackTrace(); 
    } 

其中OpenHttpConnection()函数为：

public InputStream OpenHttpConnection(String urlString) throws IOException{ 
    InputStream in = null; 
    int respobse = -1; 

    URL url = new URL(urlString); 
    URLConnection conn = url.openConnection(); 
    if(!(conn instanceof HttpURLConnection)) 
     throw new IOException("It's not HTTP connection"); 
    try{ 
     HttpURLConnection httpConn = (HttpURLConnection) conn; 
     httpConn.setAllowUserInteraction(false); 
     httpConn.setInstanceFollowRedirects(true); 
     httpConn.setRequestMethod("GET"); 
     httpConn.connect(); 

     respobse = httpConn.getResponseCode(); 
     if(respobse == HttpURLConnection.HTTP_OK){ 
      in= httpConn.getInputStream(); 
      Log.d("HTTP connection","OK"); 
     } 
    }catch (IOException e) { 
     Log.e("HTTP ERROR",e.toString()); 
     throw new IOException(); 
    } 
    return in; 
} 

Answer 1

您忽略了OpenConnection（）方法可能的空返回值。允许该方法只是抛出声明的异常并且不在内部捕获它会更好。