import java.io.BufferedReader;

 import java.io.ByteArrayOutputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.InputStreamReader;

 import java.io.PrintWriter;

 import java.net.HttpURLConnection;

 import java.net.URL;

 // Http 请求的工具类

 public class HttpUtils

 {

     private static final int TIMEOUT_IN_MILLIONS = 5000;

     public interface CallBack

     {

         void onRequestComplete(String result);

     }

     /**

      * 异步的 Get 请求

      *

      * @param urlStr

      * @param callBack

      */

     public static void doGetAsyn(final String urlStr, final CallBack callBack)

     {

         new Thread()

         {

             public void run()

             {

                 try

                 {

                     String result = doGet(urlStr);

                     if (callBack != null)

                     {

                         callBack.onRequestComplete(result);

                     }

                 } catch (Exception e)

                 {

                     e.printStackTrace();

                 }

             };

         }.start();

     }

     /**

      * 异步的 Post 请求

      * @param urlStr

      * @param params

      * @param callBack

      * @throws Exception

      */

     public static void doPostAsyn(final String urlStr, final String params,

             final CallBack callBack) throws Exception

     {

         new Thread()

         {

             public void run()

             {

                 try

                 {

                     String result = doPost(urlStr, params);

                     if (callBack != null)

                     {

                         callBack.onRequestComplete(result);

                     }

                 } catch (Exception e)

                 {

                     e.printStackTrace();

                 }

             };

         }.start();

     }

     /**

      * Get 请求，获得返回数据

      *

      * @param urlStr

      * @return

      * @throws Exception

      */

     public static String doGet(String urlStr)

     {

         URL url = null;

         HttpURLConnection conn = null;

         InputStream is = null;

         ByteArrayOutputStream baos = null;

         try

         {

             url = new URL(urlStr);

             conn = (HttpURLConnection) url.openConnection();

             conn.setReadTimeout(TIMEOUT_IN_MILLIONS);

             conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);

             conn.setRequestMethod("GET");

             conn.setRequestProperty("accept", "*/*");

             conn.setRequestProperty("connection", "Keep-Alive");

             if (conn.getResponseCode() == 200)

             {

                 is = conn.getInputStream();

                 baos = new ByteArrayOutputStream();

                 int len = -1;

                 byte[] buf = new byte[128];

                 while ((len = is.read(buf)) != -1)

                 {

                     baos.write(buf, 0, len);

                 }

                 baos.flush();

                 return baos.toString();

             } else

             {

                 throw new RuntimeException(" responseCode is not 200 ... ");

             }

         } catch (Exception e)

         {

             e.printStackTrace();

         } finally

         {

             try

             {

                 if (is != null)

                     is.close();

             } catch (IOException e)

             {

             }

             try

             {

                 if (baos != null)

                     baos.close();

             } catch (IOException e)

             {

             }

             conn.disconnect();

         }

         return null ;

     }

     /**

      * 向指定 URL 发送 POST 方法的请求

      *

      * @param url

      *            发送请求的 URL

      * @param param

      *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。

      * @return 所代表远程资源的响应结果

      * @throws Exception

      */

     public static String doPost(String url, String param)

     {

         PrintWriter out = null;

         BufferedReader in = null;

         String result = "";

         try

         {

             URL realUrl = new URL(url);

             // 打开和URL之间的连接

             HttpURLConnection conn = (HttpURLConnection) realUrl

                     .openConnection();

             // 设置通用的请求属性

             conn.setRequestProperty("accept", "*/*");

             conn.setRequestProperty("connection", "Keep-Alive");

             conn.setRequestMethod("POST");

             conn.setRequestProperty("Content-Type",

                     "application/x-www-form-urlencoded");

             conn.setRequestProperty("charset", "utf-8");

             conn.setUseCaches(false);

             // 发送POST请求必须设置如下两行

             conn.setDoOutput(true);

             conn.setDoInput(true);

             conn.setReadTimeout(TIMEOUT_IN_MILLIONS);

             conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);

             if (param != null && !param.trim().equals(""))

             {

                 // 获取URLConnection对象对应的输出流

                 out = new PrintWriter(conn.getOutputStream());

                 // 发送请求参数

                 out.print(param);

                 // flush输出流的缓冲

                 out.flush();

             }

             // 定义BufferedReader输入流来读取URL的响应

             in = new BufferedReader(

                     new InputStreamReader(conn.getInputStream()));

             String line;

             while ((line = in.readLine()) != null)

             {

                 result += line;

             }

         } catch (Exception e)

         {

             e.printStackTrace();

         }

         // 使用finally块来关闭输出流、输入流

         finally

         {

             try

             {

                 if (out != null)

                 {

                     out.close();

                 }

                 if (in != null)

                 {

                     in.close();

                 }

             } catch (IOException ex)

             {

                 ex.printStackTrace();

             }

         }

         return result;

     }

 }