Java 模拟http请求

package ln;  

  

import java.io.BufferedReader;  

import java.io.IOException;  

import java.io.InputStreamReader;  

import java.io.PrintWriter;  

import java.util.HashMap;  

import java.util.List;  

import java.util.Map;  

  

/** 

 * 用于模拟HTTP请求中GET/POST方式  

 * @author landa 

 * 

 */  

public class HttpUtils {    

    /**  

     * 发送GET请求  

     *   

     * @param url  

     *            目的地址  

     * @param parameters  

     *            请求参数，Map类型。  

     * @return 远程响应结果  

     */    

    public static String sendGet(String url, Map<String, String> parameters) {   

        String result="";  

        BufferedReader in = null;// 读取响应输入流    

        StringBuffer sb = new StringBuffer();// 存储参数    

        String params = "";// 编码之后的参数  

        try {  

            // 编码请求参数    

            if(parameters.size()==1){  

                for(String name:parameters.keySet()){  

                    sb.append(name).append("=").append(  

                            java.net.URLEncoder.encode(parameters.get(name),    

                            "UTF-8"));  

                }  

                params=sb.toString();  

            }else{  

                for (String name : parameters.keySet()) {    

                    sb.append(name).append("=").append(    

                            java.net.URLEncoder.encode(parameters.get(name),    

                                    "UTF-8")).append("&");    

                }    

                String temp_params = sb.toString();    

                params = temp_params.substring(0, temp_params.length() - 1);    

            }  

            String full_url = url + "?" + params;   

            System.out.println(full_url);   

            // 创建URL对象    

            java.net.URL connURL = new java.net.URL(full_url);    

            // 打开URL连接    

            java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL    

                    .openConnection();    

            // 设置通用属性    

            httpConn.setRequestProperty("Accept", "*/*");    

            httpConn.setRequestProperty("Connection", "Keep-Alive");    

            httpConn.setRequestProperty("User-Agent",    

                    "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");    

            // 建立实际的连接    

            httpConn.connect();    

            // 响应头部获取    

            Map<String, List<String>> headers = httpConn.getHeaderFields();    

            // 遍历所有的响应头字段    

            for (String key : headers.keySet()) {    

                System.out.println(key + "\t：\t" + headers.get(key));    

            }    

            // 定义BufferedReader输入流来读取URL的响应,并设置编码方式    

            in = new BufferedReader(new InputStreamReader(httpConn    

                    .getInputStream(), "UTF-8"));    

            String line;    

            // 读取返回的内容    

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

                result += line;    

            }    

        } catch (Exception e) {  

            e.printStackTrace();  

        }finally{  

            try {    

                if (in != null) {    

                    in.close();    

                }    

            } catch (IOException ex) {    

                ex.printStackTrace();    

            }    

        }  

        return result ;  

    }    

    

    /**   

     * 发送POST请求   

     *    

     * @param url   

     *            目的地址   

     * @param parameters   

     *            请求参数，Map类型。   

     * @return 远程响应结果   

     */    

    public static String sendPost(String url, Map<String, String> parameters) {    

        String result = "";// 返回的结果    

        BufferedReader in = null;// 读取响应输入流    

        PrintWriter out = null;    

        StringBuffer sb = new StringBuffer();// 处理请求参数    

        String params = "";// 编码之后的参数    

        try {    

            // 编码请求参数    

            if (parameters.size() == 1) {    

                for (String name : parameters.keySet()) {    

                    sb.append(name).append("=").append(    

                            java.net.URLEncoder.encode(parameters.get(name),    

                                    "UTF-8"));    

                }    

                params = sb.toString();    

            } else {    

                for (String name : parameters.keySet()) {    

                    sb.append(name).append("=").append(    

                            java.net.URLEncoder.encode(parameters.get(name),    

                                    "UTF-8")).append("&");    

                }    

                String temp_params = sb.toString();    

                params = temp_params.substring(0, temp_params.length() - 1);    

            }    

            // 创建URL对象    

            java.net.URL connURL = new java.net.URL(url);    

            // 打开URL连接    

            java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL    

                    .openConnection();    

            // 设置通用属性    

            httpConn.setRequestProperty("Accept", "*/*");    

            httpConn.setRequestProperty("Connection", "Keep-Alive");    

            httpConn.setRequestProperty("User-Agent",    

                    "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");    

            // 设置POST方式    

            httpConn.setDoInput(true);    

            httpConn.setDoOutput(true);    

            // 获取HttpURLConnection对象对应的输出流    

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

            // 发送请求参数    

            out.write(params);    

            // flush输出流的缓冲    

            out.flush();    

            // 定义BufferedReader输入流来读取URL的响应，设置编码方式    

            in = new BufferedReader(new InputStreamReader(httpConn    

                    .getInputStream(), "UTF-8"));    

            String line;    

            // 读取返回的内容    

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

                result += line;    

            }    

        } catch (Exception e) {    

            e.printStackTrace();    

        } finally {    

            try {    

                if (out != null) {    

                    out.close();    

                }    

                if (in != null) {    

                    in.close();    

                }    

            } catch (IOException ex) {    

                ex.printStackTrace();    

            }    

        }    

        return result;    

    }    

    

    /**   

     * 主函数，测试请求   

     *    

     * @param args   

     */    

    public static void main(String[] args) {    

        Map<String, String> parameters = new HashMap<String, String>();    

        parameters.put("name", "sarin");    

        String result =sendGet("http://www.baidu.com", parameters);  

        System.out.println(result);   

    }    

}