bytearraybuffer抛出indexoutofbounds异常 - 无法获得原因

Question

我通过localBroadcastmanager在Android中接收了一个bytearray。它可以正常工作，但是我将其发送到块中。

当我想合并块时，我会发现一个错误。

这是代码：

else if (message.equals(BtConstants.BtStateUpdates.BT_UPDATE_STATE_RXRAW_COMPLETE.getString())) {
    Log.i(TAG, "length [" + Integer.toString(picRaw.length()) + "] / capacity [" + Integer.toString(picRaw.capacity()) + "]");
    Log.i(TAG,"append" + Integer.toString(intent.getExtras().getByteArray(BtConstants.btBytePayload).length));              
    picRaw.append(intent.getExtras().getByteArray(BtConstants.btBytePayload), picRaw.length(), 
    intent.getExtras().getByteArray(BtConstants.btBytePayload).length);                 
    String s = "";
    try {
        s = new String(picRaw.buffer(), "US-ASCII");
    } catch (UnsupportedEncodingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    Log.i(TAG, "RCVD RAW: " + s);   
}

这是错误。首先请注意，它附加了较小的650字节，但是在附加更大的值时会失败。

**10-25 11:21:40.670: I/BluetoothService(9537): length [0] / capacity [15000]
10-25 11:21:40.675: I/BluetoothService(9537): append665**
Works FINE so far
10-25 11:21:40.680: V/BluetoothSocket.cpp(9537): readNative
10-25 11:21:40.680: I/BluetoothService(9537): RCVD RAW: �..edited out for brevity.�
10-25 11:21:40.680: D/BluetoothService(9537): Rcvd broadcast: com.test.ppt.bt_state_raw_connected 
**10-25 11:21:40.695: I/BluetoothService(9537): length [665] / capacity [15000]
10-25 11:21:40.695: I/BluetoothService(9537): append5320
10-25 11:21:40.695: D/AndroidRuntime(9537): Shutting down VM
10-25 11:21:40.695: W/dalvikvm(9537): threadid=1: thread exiting with uncaught exception (group=0x40c3c1f8)
10-25 11:21:40.730: E/AndroidRuntime(9537): FATAL EXCEPTION: main
10-25 11:21:40.730: E/AndroidRuntime(9537): java.lang.IndexOutOfBoundsException**
10-25 11:21:40.730: E/AndroidRuntime(9537):     at org.apache.http.util.ByteArrayBuffer.append(ByteArrayBuffer.java:68)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at com.test.ppt.btService.BluetoothService$1.onReceive(BluetoothService.java:217)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at android.support.v4.content.LocalBroadcastManager.executePendingBroadcasts(LocalBroadcastManager.java:297)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at android.support.v4.content.LocalBroadcastManager.access$000(LocalBroadcastManager.java:46)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at android.support.v4.content.LocalBroadcastManager$1.handleMessage(LocalBroadcastManager.java:116)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at android.os.Looper.loop(Looper.java:137)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at android.app.ActivityThread.main(ActivityThread.java:4507)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at java.lang.reflect.Method.invokeNative(Native Method)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at java.lang.reflect.Method.invoke(Method.java:511)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
10-25 11:21:40.730: E/AndroidRuntime(9537):     at dalvik.system.NativeStart.main(Native Method)

初始容量为15000-应该足够。

Answer 1

  try {
                s = new String(picRaw.buffer(), "US-ASCII");
            } 
catch (ArrayIndexOutOfBoundsException e) {
            // TODO: handle exception
        }
        catch (IndexOutOfBoundsException e) {
            // TODO: handle exception
        }
catch (UnsupportedEncodingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

我希望以上代码对您有所帮助。

Answer 2

我想我在这里找到了解决方案。bytearraybuffer。应用程序的工作方式与我预期的不同。引用此新文档：

void append（char [] b，int off，int len）

      Appends len chars to this buffer from the given source array starting at index off.

从char [] b中的索引开始。附加始终是在bytearraybuffer的末尾完成的。

因此，我的代码应该看起来像这样：

picRaw.append(intent.getExtras().
    getByteArray(BtConstants.btBytePayload), picRaw.length(), 
        intent.getExtras().getByteArray(BtConstants.btBytePayload).length);