如何停止HttpURLConnection.getInputStream()？

Question

以下是我的代码:

private HttpURLConnection connection;
private InputStream is;

public void upload() {
    try {
        URL url = new URL(URLPath);
        connection = (HttpURLConnection) url.openConnection();
        connection.setConnectTimeout(30000);
        connection.setReadTimeout(30000);
        connection.setDoInput(true);
        connection.setUseCaches(false);
        connection.connect();
        is = connection.getInputStream();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public void stopupload() {
    connection = null;
    is = null;
}

当我上传文件时,该行将is = connection.getInputStream();花费大量时间来回复.所以我想实现一个停止功能stopupload().但是如果我stopupload()在代码处理时调用is = connection.getInputStream();,它仍然需要等待它的回复.

我希望在实施时立即停止等待stopupload().我该怎么做？

Answer 1

但是，如果我stopupload()在代码处理 line 时调用is = connection.getInputStream();，它仍然需要等待其回复。

从HoneyComb开始，所有网络操作都不允许在主线程上执行。为了避免出现NetworkOnMainThreadException，您可以使用Threador AsyncTask。

我想在实现 stopupload() 时立即停止等待。我该怎么做？

下面的代码让用户在 2 秒后停止上传，但您可以相应地修改睡眠时间（应小于 5 秒）。

上传：

public void upload() {
    try {
        URL url = new URL(URLPath);
        connection = (HttpURLConnection) url.openConnection();
        connection.setConnectTimeout(30000);
        connection.setReadTimeout(30000);
        connection.setDoInput(true);
        connection.setUseCaches(false);
        connection.connect();
        // run uploading activity within a Thread
        Thread t = new Thread() {
            public void run() {
                is = connection.getInputStream();
                if (is == null) {
                    throw new RuntimeException("stream is null");
                }
                // sleep 2 seconds before "stop uploading" button appears
                mHandler.postDelayed(new Runnable() {
                    public void run() {
                        mBtnStop.setVisibility(View.VISIBLE);
                    }
                }, 2000);
            }
        };
        t.start();
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (is != null) {
            try {
                is.close();
            } catch (IOException e) {
            }
        }
        if (connection != null) {
            connection.disconnect();
        }
    }
}

创建时：

@Override
public void onCreate(Bundle savedInstanceState) {
    // more codes...
    Handler mHandler = new Handler();
    mBtnStop = (Button) findViewById(R.id.btn_stop);
    mBtnStop.setBackgroundResource(R.drawable.stop_upload);
    mBtnStop.setOnClickListener(mHandlerStop);
    mBtnStop.setVisibility(View.INVISIBLE);

    View.OnClickListener mHandlerStop = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            stopUpload(); // called when "stop upload" button is clicked
        }
    };

    // more codes...
}