在Android中使用HttpURLConnection从url获取xml答案

【问题标题】：Getting xml from url with HttpURLConnection in Android在Android中使用HttpURLConnection从url获取xml
【发布时间】：2015-11-17 14:36:45
【问题描述】：

我使用支持 Apache HTTP 客户端从 url 获取 xml。

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

    try {
        // defaultHttpClient
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);

        HttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        xml = EntityUtils.toString(httpEntity, "UTF-8");

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    // return XML
    return xml;
}

Google 宣布从 Android 6.0 开始取消对 Apache HTTP 客户端的支持，并改用 HttpURLConnection 类。最后，我想使用 HttpURLConnection 从 url 获取 xml，但我不知道！有人可以帮助我:)

【问题讨论】：

标签： android xml httpurlconnection

【解决方案1】：

作为一般提示，由于您没有触及它，我建议在 IntentService 中执行所有 Web 请求，这样它就不会阻塞您的 UI 线程。至于答案，您可以像这样使用 HttpURLConnection

public String getXMLFromUrl(String url) {
    BufferedReader br = null;
    try {
        HttpURLConnection conn = (HttpURLConnection)(new URL(url)).openConnection();
        br = new BufferedReader(new InputStreamReader(conn.getInputStream()));

        String line;
        final StringBuilder sb = new StringBuilder();
        while ((line = br.readLine()) != null) {
            sb.append(line).append("\n");
        }

        return sb.toString();
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    } finally {
        try {
            if (br != null) br.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

这应该不会太难理解，因为代码更改很少，但如果您有任何问题，我很乐意听到他们的声音:)

【讨论】：

【解决方案2】：

您可以尝试修改或使用它作为您的要求如下：

// Create a new UrlConnection
            URL postUrl = null;
            try {
                postUrl = new URL("Your Url");
            } catch (MalformedURLException e) {
                e.printStackTrace();
            }
            // Open the created connection to server.
            HttpURLConnection httpURLConnection = null;
            try {
                httpURLConnection = (HttpURLConnection) postUrl.openConnection();
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
            // Set up the post parameters
            httpURLConnection.setReadTimeout(10000);
            httpURLConnection.setConnectTimeout(15000);

            try {
                httpURLConnection.setRequestMethod("POST or GET");
            } catch (ProtocolException e) {
                e.printStackTrace();
                // Server Error
                return false;
            }

            httpURLConnection.setDoInput(true);
            httpURLConnection.setDoOutput(true);
            httpURLConnection.setRequestProperty("Content-Type", "text/xml");

            OutputStream outputStream = null;

            try {
                outputStream = httpURLConnection.getOutputStream();
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
            // Create a writer to write on the output stream.
            BufferedWriter writer = null;
            try {
                writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
                return false;
            }
            // Send the post request
            try {
                writer.write();
                writer.flush();
                writer.close();
                outputStream.close();
                httpURLConnection.connect();
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
            // Get response code
            int response = 0;

            try {
                response  = httpURLConnection.getResponseCode();
            } catch (IOException e) {
                e.printStackTrace();
            }
            // Get the Response
            String responseData = "";
            if(response == HttpURLConnection.HTTP_OK){//Response is okay
                String line = "";
                try {
                    BufferedReader reader = new BufferedReader(new InputStreamReader(httpURLConnection.getInputStream()));
                    while ((line=reader.readLine()) != null) {
                        responseData += line;
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            else{
                // Server is down or webserver is changed.
                return false;
            }
            return true;

【讨论】：

【解决方案3】：

您可能需要包含一些额外的库

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

如果你使用android studio，它可以为你下载jar文件，只需使用Alt+Enter帮助

【讨论】：