java请求HTTP

 /**
  * get方式请求接口链接
  * @param strUrl 链接地址
  * @param params 参数
  * @return
  */
 public static String doGet(String strUrl ,Map<String, Object> params) {
  String result = "";
  try {
   //判断参数params是否为空
   if (null != params && params.size() > 0 ) {
    strUrl += "?";
    for (Entry<String, Object> m : params.entrySet()) {
     String key = m.getKey().toString();
     String value = m.getValue().toString();
     strUrl += key+"="+URLEncoder.encode(value, "UTF-8")+"&";
    }
    strUrl = strUrl.substring(0, strUrl.lastIndexOf("&"));
   }
   URL url = new URL(strUrl);
   // 使用HttpURLConnection打开链接
   HttpURLConnection conn = (HttpURLConnection) url.openConnection();
   // 连接url引用资源的链接
   conn.connect();
   // 以流的形式获取到链接的内容
   InputStream stream = conn.getInputStream();
   int len = 0;
   byte[] buffer = new byte[1024];// 缓存
   ByteArrayOutputStream outStream = new ByteArrayOutputStream();
   while ((len = stream.read(buffer)) != -1) {// 直到读到文件结束
    outStream.write(buffer, 0, len);
   }
   byte[] data = outStream.toByteArray();// 得到文件的二进制数据
   outStream.close();
   stream.close();

   result = new String(data,"UTF-8");
   conn.disconnect();
   stream.close();
  } catch (Exception e) {
   e.printStackTrace();
  }

  return result;
 }

 /**
  *
  * @Description: post方式请求接口链接
  * @param @param strUrl
  * @param @param params
  * @param @return  
  * @return String 
  * @throws
  * @author demo
  * @date 2014年10月31日
  */
 public static String doPost(String strUrl, Map<String, Object> params) {
  String result = "";
  try {
   URL url = new URL(strUrl);
   // 使用HttpURLConnection打开连接
   HttpURLConnection conn = (HttpURLConnection) url.openConnection();
   conn.setRequestMethod("POST");// 设置 URL 请求的方法
   conn.setDoInput(true);// 允许接收输入
   conn.setDoOutput(true);// 允许接收输出
   // conn.setRequestProperty("Content-Type",
   // "application/x-www-form-urlencoded");
   conn.connect();// 打开到此 URL 引用的资源的通信链接

   // 用DataOutputStream.writeBytes(content)将请求参数写入进去
   DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
   String str = "";
   //判断参数params是否为空
   if (null != params && params.size() > 0) {
    for (Entry<String, Object> m : params.entrySet()) {
     String key = m.getKey().toString();
     String value = m.getValue().toString();
     str += key+"="+URLEncoder.encode(value, "UTF-8")+"&";
    }
    System.out.println(str.substring(0, str.lastIndexOf("&")));
    dos.writeBytes(str.substring(0, str.lastIndexOf("&")));
    dos.close();
   }
   // 获取该连接的输入
   InputStream stream = conn.getInputStream();
   byte[] buffer = new byte[1024];// 缓存
   int len = 0;
   ByteArrayOutputStream outStream = new ByteArrayOutputStream();
   while ((len = stream.read(buffer)) != -1) {// 直到读到文件结束
    outStream.write(buffer, 0, len);
   }
   byte[] data = outStream.toByteArray();// 得到文件的二进制数据
   outStream.close();
   stream.close();

   result = new String(data,"UTF-8");
   conn.disconnect();// 指示服务器近期不太可能有其他请求
   stream.close();
  } catch (Exception e) {
   e.printStackTrace();
  }
  return result;
 }