java发送http的get、post请求
(转自http://www.cnblogs.com/zhuawang/archive/2012/12/08/2809380.html)
Http请求类:
1 package com.study.test; 2 3 import java.io.BufferedReader; 4 import java.io.IOException; 5 import java.io.InputStreamReader; 6 import java.io.PrintWriter; 7 import java.net.URL; 8 import java.net.URLConnection; 9 import java.util.List; 10 import java.util.Map; 11 12 public class HttpRequest { 13 /** 14 * 向指定URL发送GET方法的请求 15 * 16 * @param url 发送请求的URL 17 * @param param 请求参数,请求参数应该是 name1=value1&name2=value2 的形式。 18 * @return URL 所代表远程资源的响应结果 19 */ 20 public static String sendGet(String url, String param) { 21 String result = ""; 22 BufferedReader in = null; 23 try { 24 String urlNameString = url + "?" + param; 25 URL realUrl = new URL(urlNameString); 26 // 打开和URL之间的连接 27 URLConnection connection = realUrl.openConnection(); 28 // 设置通用的请求属性 29 connection.setRequestProperty("accept", "*/*"); 30 connection.setRequestProperty("connection", "Keep-Alive"); 31 connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); 32 // 建立实际的连接 33 connection.connect(); 34 // 获取所有响应头字段 35 Map<String, List<String>> map = connection.getHeaderFields(); 36 // 遍历所有的响应头字段 37 for (String key : map.keySet()) { 38 System.out.println(key + "--->" + map.get(key)); 39 } 40 // 定义 BufferedReader输入流来读取URL的响应 41 in = new BufferedReader(new InputStreamReader( 42 connection.getInputStream())); 43 String line; 44 while ((line = in.readLine()) != null) { 45 result += line; 46 } 47 } catch (Exception e) { 48 System.out.println("发送GET请求出现异常!" + e); 49 e.printStackTrace(); 50 } 51 // 使用finally块来关闭输入流 52 finally { 53 try { 54 if (in != null) { 55 in.close(); 56 } 57 } catch (Exception e2) { 58 e2.printStackTrace(); 59 } 60 } 61 return result; 62 } 63 64 /** 65 * 向指定 URL 发送POST方法的请求 66 * 67 * @param url 发送请求的 URL 68 * @param param 请求参数,请求参数应该是 name1=value1&name2=value2 的形式。 69 * @return 所代表远程资源的响应结果 70 */ 71 public static String sendPost(String url, String param) { 72 PrintWriter out = null; 73 BufferedReader in = null; 74 String result = ""; 75 try { 76 URL realUrl = new URL(url); 77 // 打开和URL之间的连接 78 URLConnection conn = realUrl.openConnection(); 79 // 设置通用的请求属性 80 conn.setRequestProperty("accept", "*/*"); 81 conn.setRequestProperty("connection", "Keep-Alive"); 82 conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); 83 // 发送POST请求必须设置如下两行 84 conn.setDoOutput(true); 85 conn.setDoInput(true); 86 // 获取URLConnection对象对应的输出流 87 out = new PrintWriter(conn.getOutputStream()); 88 // 发送请求参数 89 out.print(param); 90 // flush输出流的缓冲 91 out.flush(); 92 // 定义BufferedReader输入流来读取URL的响应 93 in = new BufferedReader( 94 new InputStreamReader(conn.getInputStream())); 95 String line; 96 while ((line = in.readLine()) != null) { 97 result += line; 98 } 99 } catch (Exception e) { 100 System.out.println("发送 POST 请求出现异常!" + e); 101 e.printStackTrace(); 102 } 103 //使用finally块来关闭输出流、输入流 104 finally { 105 try { 106 if (out != null) { 107 out.close(); 108 } 109 if (in != null) { 110 in.close(); 111 } 112 } catch (IOException ex) { 113 ex.printStackTrace(); 114 } 115 } 116 return result; 117 } 118 }
调用方法:
public static void main(String[] args) { //发送 GET 请求 String s = HttpRequest.sendGet("http://localhost:8080/rings/receive", "key=123&v=456"); System.out.println(s); //发送 POST 请求 String sr = HttpRequest.sendPost("http://localhost:8080/rings/receive", "key=123&v=456"); System.out.println(sr); }