http utils 工具类 经典

package com.lhjx.utils;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.io.PrintWriter;import java.net.URL;import java.net.URLConnection;import java.net.URLEncoder;import java.util.Map;    /**  * @author Administrator  *  */  public class HttpUtils {        /**      * 使用Get方式获取数据      *       * @param url      *            URL包括参数，http://HOST/XX?XX=XX&XXX=XXX      * @param charset      * @return      */      public static String sendGet(String url, String charset) {          String result = "";          BufferedReader in = null;          try {              URL realUrl = new URL(url);              // 打开和URL之间的连接              URLConnection connection = realUrl.openConnection();              // 设置通用的请求属性              connection.setRequestProperty("accept", "*/*");              connection.setRequestProperty("connection", "Keep-Alive");              connection.setRequestProperty("user-agent",                      "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");              // 建立实际的连接              connection.connect();              // 定义 BufferedReader输入流来读取URL的响应              in = new BufferedReader(new InputStreamReader(                      connection.getInputStream(), charset));              String line;              while ((line = in.readLine()) != null) {                  result += line;              }          } catch (Exception e) {              System.out.println("发送GET请求出现异常！" + e);              e.printStackTrace();          }          // 使用finally块来关闭输入流          finally {              try {                  if (in != null) {                      in.close();                  }              } catch (Exception e2) {                  e2.printStackTrace();              }          }          return result;      }        /**       * POST请求，字符串形式数据       * @param url 请求地址       * @param param 请求数据       * @param charset 编码方式       */      public static String sendPostUrl(String url, String param, String charset) {            PrintWriter out = null;          BufferedReader in = null;          String result = "";          try {              URL realUrl = new URL(url);              // 打开和URL之间的连接              URLConnection conn = realUrl.openConnection();              // 设置通用的请求属性              conn.setRequestProperty("accept", "*/*");              conn.setRequestProperty("connection", "Keep-Alive");              conn.setRequestProperty("user-agent",                      "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");              // 发送POST请求必须设置如下两行              conn.setDoOutput(true);              conn.setDoInput(true);              // 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(), charset));              String line;              while ((line = in.readLine()) != null) {                  result += line;              }          } catch (Exception e) {              System.out.println("发送 POST 请求出现异常！" + 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;      }      /**       * POST请求，Map形式数据       * @param url 请求地址       * @param param 请求数据       * @param charset 编码方式       */      public static String sendPost(String url, Map<String, String> param,              String charset) {            StringBuffer buffer = new StringBuffer();          if (param != null && !param.isEmpty()) {              for (Map.Entry<String, String> entry : param.entrySet()) {                  buffer.append(entry.getKey()).append("=")                          .append(URLEncoder.encode(entry.getValue()))                          .append("&");                }          }          buffer.deleteCharAt(buffer.length() - 1);            PrintWriter out = null;          BufferedReader in = null;          String result = "";          try {              URL realUrl = new URL(url);              // 打开和URL之间的连接              URLConnection conn = realUrl.openConnection();              // 设置通用的请求属性              conn.setRequestProperty("accept", "*/*");              conn.setRequestProperty("connection", "Keep-Alive");              conn.setRequestProperty("user-agent",                      "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");              // 发送POST请求必须设置如下两行              conn.setDoOutput(true);              conn.setDoInput(true);              // 获取URLConnection对象对应的输出流              out = new PrintWriter(conn.getOutputStream());              // 发送请求参数              out.print(buffer);              // 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(), charset));              String line;              while ((line = in.readLine()) != null) {                  result += line;              }          } catch (Exception e) {              System.out.println("发送 POST 请求出现异常！" + 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;      }        public static void main(String[] args) {      }  }