Question

我正在尝试连接到我必须获取数据的互联网，如果时间超过5秒连接我必须完成该过程＆amp;继续离线工作。
一切都运行正常，当互联网不可用时，有时大约需要10秒到return，现在当时间超过时间限制时，我必须返回xml == null;，
我不想在异步任务

中执行此操作

    public String getUrlData(String url) {
    String xml = null;

    DefaultHttpClient httpClient = new DefaultHttpClient();
    HttpPost httpPost = new HttpPost(url);
    System.out.println("waiting");
    HttpResponse httpResponse;

    try {
        // start the timer here

        httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        xml = EntityUtils.toString(httpEntity);

        // check if the timer has exceeded by "if else"
        // move to "return xml;" Manually when exceeds 5sec, but how?

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

}

this answer之后编辑的代码

public String getUrlData(String url) {
    String xml = null;

    final int TIMEOUT_MILLISEC = 5000; // 5 seconds

    HttpParams httpParams = new BasicHttpParams();
    HttpConnectionParams.setConnectionTimeout(httpParams, TIMEOUT_MILLISEC);
    HttpConnectionParams.setSoTimeout(httpParams, TIMEOUT_MILLISEC);

    DefaultHttpClient httpClient = new DefaultHttpClient(httpParams);
    HttpPost httpPost = new HttpPost(url);
    System.out.println("waiting");
    HttpResponse httpResponse;

    try {
        // start the timer here
        System.out.println("Started");
        httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        xml = EntityUtils.toString(httpEntity);

    } catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    System.out.println("Ended");
    return xml;

}

LogCat Here＆gt;＆gt; 20 Secs

Answer 1

您需要做的就是为您的连接定义超时限制。例如：

final int TIMEOUT_MILLISEC = 5000;  // 5 seconds

HttpParams httpParams = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParams, TIMEOUT_MILLISEC);
HttpConnectionParams.setSoTimeout(httpParams, TIMEOUT_MILLISEC);

HttpClient httpClient = new DefaultHttpClient(httpParams);

然后，使用httpClient与使用它的方式相同。

修改

public String getUrlData(String url) { String xml = null; final int TIMEOUT_MILLISEC = 5000; // 5 seconds HttpParams httpParams = new BasicHttpParams(); HttpConnectionParams.setConnectionTimeout(httpParams, TIMEOUT_MILLISEC); HttpConnectionParams.setSoTimeout(httpParams, TIMEOUT_MILLISEC); DefaultHttpClient httpClient = new DefaultHttpClient(httpParams); HttpPost httpPost = new HttpPost(url); System.out.println("waiting"); HttpResponse httpResponse; try { // start the timer here httpResponse = httpClient.execute(httpPost); HttpEntity httpEntity = httpResponse.getEntity(); xml = EntityUtils.toString(httpEntity); // check if the timer has exceeded by "if else" // move to "return xml;" Manually when exceeds 5sec, but how? } catch (ClientProtocolException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return xml; }

Answer 2

这个怎么样：

Thread thread = new Thread() {
  @Override
  public void run() {
    // do the downloading thing..
  }
};
thread.start();
thread.join(5000);

Answer 3

这只是一个想法，但你可以设置一个延迟的runnable并在5秒后检查文件是否有任何大小。

Answer 4

 HttpParams params = new BasicHttpParams();

    // Turn off stale checking.  Our connections break all the time anyway,
    // and it's not worth it to pay the penalty of checking every time.
    HttpConnectionParams.setStaleCheckingEnabled(params, false);

    HttpConnectionParams.setConnectionTimeout(params, SOCKET_OPERATION_TIMEOUT);
    HttpConnectionParams.setSoTimeout(params, SOCKET_OPERATION_TIMEOUT);
    HttpConnectionParams.setSocketBufferSize(params, 8192);

    // Don't handle redirects -- return them to the caller.  Our code
    // often wants to re-POST after a redirect, which we must do ourselves.
    HttpClientParams.setRedirecting(params, false);

    // Use a session cache for SSL sockets
    SSLSessionCache sessionCache = context == null ? null : new SSLSessionCache(context);

    // Set the specified user agent and register standard protocols.
    HttpProtocolParams.setUserAgent(params, userAgent);
    SchemeRegistry schemeRegistry = new SchemeRegistry();
    schemeRegistry.register(new Scheme("http",
            PlainSocketFactory.getSocketFactory(), 80));
    schemeRegistry.register(new Scheme("https",
            SSLCertificateSocketFactory.getHttpSocketFactory(
            SOCKET_OPERATION_TIMEOUT, sessionCache), 443));

    ClientConnectionManager manager =
            new ThreadSafeClientConnManager(params, schemeRegistry);

    // We use a factory method to modify superclass initialization
    // parameters without the funny call-a-static-method dance.
    return new AndroidHttpClient(manager, params);

根据您的需要更改SOCKET_OPERATION_TIMEOUT值。

Answer 5

此代码可以帮助您

上一个答案的代码是好的

final int TIMEOUT_MILLISEC = 5000;  // 5 seconds

HttpParams httpParams = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParams, TIMEOUT_MILLISEC);
HttpConnectionParams.setSoTimeout(httpParams, TIMEOUT_MILLISEC);

HttpClient httpClient = new DefaultHttpClient(httpParams);

只有当您尝试执行请求时，您才需要关心另外3个例外 SocketTimeoutException，UnknownHostException，ConnectTimeoutException

所以赶上这3个例外。

尝试只使用几秒钟的Internet连接

5 个答案: