Android HttpEntityUtils OutOfMemoryException

Question

我正在开发一个连接到网络服务器并接收二进制数据的项目。我的问题是当我从网络服务器下载数据时。如果我发送登录请求或激活某些设置，则没有问题。但是，当我发送下载二进制数据的请求时，它向我抛出一个 OutOfMemoryException。这是我正在使用的代码：

public byte[] activateColl(int index) {
        createCancelProgressDialog("","Communcating with you...","Cancel");

        byte[] buffer = new byte[1024];
        try {
                httpclient = new DefaultHttpClient();
                httppost = new HttpPost("http://www.rpc.frbr.com");

                TelephonyManager tm = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);
                String deviceId = tm.getDeviceId();
                Log.w("device_identificator","device_identificator : "+deviceId);
                String resolution = Integer.toString(getWindow().getWindowManager().getDefaultDisplay().getWidth())+ "x" +
                                             Integer.toString(getWindow().getWindowManager().getDefaultDisplay().getHeight());
                Log.w("device_resolution","device_resolution : "+resolution);
                String version = "Android " + Build.VERSION.RELEASE;
                Log.w("device_os_type","device_os_type : "+version);
                Log.w("device_identification_string","device_identification_string : "+version);
                String locale = getResources().getConfiguration().locale.toString();
                Log.w("set_locale","set_locale : "+locale);
                String clientApiVersion = null;

                PackageManager pm = this.getPackageManager();
                PackageInfo packageInfo = pm.getPackageInfo(this.getPackageName(), 0);
                clientApiVersion = packageInfo.versionName;
                Log.w("client_api_ver","client_api_ver : "+clientApiVersion);

                hash = getAuthHash();

                TelephonyManager tMgr =(TelephonyManager)this.getSystemService(Context.TELEPHONY_SERVICE);
                phoneNumber = tMgr.getLine1Number();
                Log.i("Phone","Phone Number : "+phoneNumber);

                Log.w("INDEX","INDEXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX : "+Integer.toString(index));

                String timestampSQL = "SELECT dbTimestamp FROM users";
                Cursor cursor = systemDbHelper.executeSQLQuery(timestampSQL);
                if(cursor.getCount()==0){
                    Log.i("Cursor","TimeStamp Cursor Empty!");
                } else if(cursor.getCount()>0){
                    cursor.moveToFirst();
                    timeStamp = cursor.getString(cursor.getColumnIndex("dbTimestamp"));
                }


                postParameters = new ArrayList<NameValuePair>();
                postParameters.add(new BasicNameValuePair("debug_data","1"));
                postParameters.add(new BasicNameValuePair("client_auth_hash", hash));
                postParameters.add(new BasicNameValuePair("timestamp", timeStamp));
                postParameters.add(new BasicNameValuePair("mobile_phone", phoneNumber));
                postParameters.add(new BasicNameValuePair("activate_collections",Integer.toString(index)));
                postParameters.add(new BasicNameValuePair("device_identificator", deviceId));
                postParameters.add(new BasicNameValuePair("device_resolution", resolution));

                httppost.setEntity(new UrlEncodedFormEntity(postParameters));

                HttpResponse response = httpclient.execute(httppost);
                Log.w("Response ","Status line : "+ response.getStatusLine().toString());

                buffer = EntityUtils.toByteArray(response.getEntity());

            } catch (ParseException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (NameNotFoundException e) {
                e.printStackTrace();
            }
                return buffer;
        }

LogCat 中的错误：

10-17 17:53:00.198: ERROR/AndroidRuntime(15486): java.lang.OutOfMemoryError
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at org.apache.http.util.ByteArrayBuffer.expand(ByteArrayBuffer.java:57)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at org.apache.http.util.ByteArrayBuffer.append(ByteArrayBuffer.java:75)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at org.apache.http.util.EntityUtils.toByteArray(EntityUtils.java:80)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at com.stampii.stampii.synchronization.Synchronization.deactivateColl(Synchronization.java:843)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at com.stampii.stampii.synchronization.Synchronization.onCreate(Synchronization.java:116)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1069)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2751)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2803)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.app.ActivityThread.access$2300(ActivityThread.java:135)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2136)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.os.Looper.loop(Looper.java:144)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at android.app.ActivityThread.main(ActivityThread.java:4937)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at java.lang.reflect.Method.invokeNative(Native Method)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at java.lang.reflect.Method.invoke(Method.java:521)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-17 17:53:00.198: ERROR/AndroidRuntime(15486):     at dalvik.system.NativeStart.main(Native Method)

任何想法如何解决这个问题？我尝试将缓冲区的大小增加到 50*1024，但仍然没有帮助。

编辑：该行抛出错误：

buffer = EntityUtils.toByteArray(response.getEntity());

Answer 1

在 Android 上，堆大小有限，当您尝试解码实体时，堆大小会耗尽。我认为您需要使用 http 分块将数据发送到客户端（或者出现问题，EntityUtils 认为它​​们需要更大的数组。问题是字节数​​组太大而不是太小。看看这个帖子：

1. 检测 Android 中的应用程序堆大小
2. 不同手机/设备和操作系统版本上的 Android 堆大小

Answer 2

好的，试试这个..

HttpResponse response = httpclient.execute(httppost);         
 // get response entity 
 HttpEntity entity = response.getEntity();          
 // convert entity response to string  
   if (entity != null) 
    {      
     InputStream is = entity.getContent();     
     // convert stream to string    
     result = convertStreamToString(is);      
     result = result.replace("\n", "");     

   } 

对于将 InputStream 转换为 String

public String convertStreamToString(InputStream inputStream)
{
 BufferedReader r = new BufferedReader(new InputStreamReader(inputStream));
 StringBuilder total = new StringBuilder();
 String line;
  while ((line = r.readLine()) != null) {
    total.append(line);
  }
return total.toString();
}

或

使用 Apache Commons 库 (org.apache.commons.io.IOUtils)。

  String total = IOUtils.toString(inputStream);

或者只是写入临时文件，

  HttpEntity.writeTo(OutputStream);

按照用户 Philipp Reichart 的建议，从 org.apache.http.util 包中写入；

EntityUtils.toString(); 

是允许使用字符串转换的编码格式的方法。

让我知道您仍然遇到OutOfMemory Error。

谢谢。