无法解析主机 Android

Question

我想使用本地代理从我的 Android 设备发送一个 http 请求。 在详细说明我的问题之前，我想让你知道这在我尝试过的每台设备上都运行良好，除了在 Android 4.0.4 下运行的 Xperia arc S 和 Xperia T。我在两台设备上都有数据连接，而且都在工作！

我使用了DefaultHttpClient 实例来发送我的请求，但是当代码到达该部分时：

client.execute(request.target, request.post);

它崩溃说以下错误：

02-21 15:37:25.677: W/System.err(1926): java.net.UnknownHostException: Unable to resolve host "192.168.010.200": No address associated with hostname
02-21 15:37:25.681: W/System.err(1926):     at java.net.InetAddress.lookupHostByName(InetAddress.java:426)
02-21 15:37:25.681: W/System.err(1926):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
02-21 15:37:25.681: W/System.err(1926):     at java.net.InetAddress.getAllByName(InetAddress.java:220)
02-21 15:37:25.681: W/System.err(1926):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:143)
02-21 15:37:25.681: W/System.err(1926):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
02-21 15:37:25.681: W/System.err(1926):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
02-21 15:37:25.681: W/System.err(1926):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
02-21 15:37:25.681: W/System.err(1926):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:580)
02-21 15:37:25.681: W/System.err(1926):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:534)
02-21 15:37:25.681: W/System.err(1926):     at com.myapp.mms.sender.WapClient.execute(WapClient.java:59)

在上面的错误日志中，本地IP是我的本地代理主机。

这是我的全部代码：

public Response execute(PostRequest request) throws Exception
{
    // Set proxy and route
    this.params = client.getParams();
    if (isProxySet) ConnRouteParams.setDefaultProxy(params, new HttpHost(this.host, this.port));        
    request.post.setParams(params);

    // Set header
    request.post.addHeader("Accept", "*/*, application/vnd.wap.mms-message, application/vnd.wap.sic");
    request.post.addHeader("Accept-Language", getCurrentAcceptLanguage(Locale.getDefault()));

    // Execute the request
    HttpResponse httpResponse = client.execute(request.target, request.post);

    // Create the object that will receive the response
    Response response = new Response();

    // Get the response code
    StatusLine status = httpResponse.getStatusLine();
    response.code = status.getStatusCode();

    // Get the response body
    byte[] responseBody = null;
    HttpEntity entity = httpResponse.getEntity();
    if (entity != null)
    {
        if (entity.getContentLength() > 0)
        {
            responseBody = new byte[(int)entity.getContentLength()];
            DataInputStream dis = new DataInputStream(entity.getContent());
            dis.readFully(responseBody);
            dis.close();
        }
        entity.consumeContent();
    }
    response.body = responseBody;

    return response;
}

有没有办法绕过这个仅在 Android 4.0.4 下出现的错误，还是我做错了？

或者有没有办法在不调用 InetAddress.getByName 的情况下做同样的事情？

Answer 1

我找到了一种似乎适用于我拥有的每台设备的方法：

    URL url = new URL(apn);

    // Set-up proxy
    Log.d(TAG, "Setting up proxy (" + host + ":" + port + ")");
    Properties systemProperties = System.getProperties();
    systemProperties.setProperty("http.proxyHost", host);
    systemProperties.setProperty("http.proxyPort", String.valueOf(port));
    systemProperties.setProperty("http.keepAlive", "false");

    // Open connection
    HttpURLConnection connection = (HttpURLConnection) url.openConnection();

    // Use the URL connection for output
    connection.setUseCaches(false);
    connection.setDoOutput(true);

    // Set the timeouts
    connection.setConnectTimeout(TIMEOUT);
    connection.setReadTimeout(TIMEOUT);

    // Sends the request
    connection.setRequestProperty("Content-Type", "application/vnd.wap.mms-message");
    connection.setRequestProperty("Content-Length", Integer.toString(mms.length));

    // Connect to the MMSC
    Log.d(TAG, "Connecting to APN " + apn);
    connection.connect();

    try
    {
        // Upload mms as bytes array
        Log.d(TAG, "Uploading data (Size: " + mms.length);
        OutputStream out = connection.getOutputStream();
        out.write(mms);
        out.flush();
        out.close();

        // Wait for the response
        Log.d(TAG, "Response code is " + connection.getResponseCode());

        if (connection.getContentLength() >= 0)
        {
            Log.d(TAG, "Reading response ...");
            byte[] responseArray = new byte[connection.getContentLength()];
            DataInputStream i = new DataInputStream(connection.getInputStream());
            int b = 0;
            int index = 0;
            while ((b = i.read()) != -1)
            {
                responseArray[index] = (byte) b;
                index++;
            }
            i.close();

            // Close the connection
            Log.d(TAG, "[MMS Sender] Disconnecting ...");
            connection.disconnect();
        }
        else
        {
            return false;
        }
    }
    catch (Exception e)
    {
        e.printStackTrace();
    }


    return false;

我希望这会帮助一些有同样错误的人。