package cn.internet.demo;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;
import java.util.Map;
public class GetPostTest {
/**
* 向指定URL发送GET方式请求
*/
public static String sendGet(String url,String param){
String result = "";
String urlName = url+"?"+param;
try {
URL realUrl = new URL(urlName);
// 打开联接
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)");
// 建立实际的联接
conn.connect();
System.out.println("文件大小："+conn.getContentLength());
// 获取所有的相应头字段
Map<String, List<String>> map = conn.getHeaderFields();
// 遍历所有的相应头字段
for (String key:map.keySet()) {
System.out.println(key+"--->"+map.get(key));
}
// 定义 BufferedReader输入流来读取URL的相应
try(BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream(),"utf-8"))){
String line;
while ((line = in.readLine())!=null) {
result += "\n"+line;
}
}
} catch (Exception e) {
System.out.println("发送Get请求出现异常！");
e.printStackTrace();
}
return result;
}
public static String sendPost(String url,String param){
String result = "";
try {
URL realUrl = new URL(url);
// 打开联接
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
try(PrintWriter out = new PrintWriter(conn.getOutputStream())){
out.print(param); // 发送请求参数
out.flush(); // flush输出流的缓冲
}
// 定义 BufferedReader输入流来读取URL的相应
try(BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream(),"utf-8"))){
String line;
while ((line = in.readLine())!=null) {
result += "\n"+line;
}
}
// 获取所有的相应头字段
Map<String, List<String>> map = conn.getHeaderFields();
// 遍历所有的相应头字段
for (String key:map.keySet()) {
System.out.println(key+"--->"+map.get(key));
}
} catch (Exception e) {
System.out.println("发送Get请求出现异常！");
e.printStackTrace();
}
return result;
}
public static void main(String[] args) {
// String s = GetPostTest.sendGet("http://localhost:8080/NetWork_Code/index.jsp", "name=rapido&pwd=liying5201314");
// System.out.println("get: "+s);
String s = GetPostTest.sendGet("http://localhost:8080/NetWork_Code/data.json", null);
System.out.println("get: "+s);
// String s2 = GetPostTest.sendPost("http://localhost:8080/NetWork_Code/index.jsp", "name=rapido&pwd=liying5201314");
// System.out.println("post: "+s2);
}
}
在Web应用程序中测试一个index.jsp页面联接
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
System.out.println("name：" + name + "，pwd：" + pwd);
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
</head>
<body>
This is my JSP page.
<h1 style="color:red">用户名：<%=name %>, 密码：<%=pwd %></h1>
<br>
</body>
</html>
启动服务后，执行main方法返回以下类型数据文件大小：539 null--->[HTTP/1.1 200 OK] Date--->[Sat, 30 May 2015 14:57:58 GMT] Content-Length--->[539] Set-Cookie--->[JSESSIONID=CD19ECBE035FDC1287CE22AD5CEF6DBA; Path=/NetWork_Code/; HttpOnly] Content-Type--->[text/html;charset=UTF-8] Server--->[Apache-Coyote/1.1] get: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>My JSP 'index.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> </head> <body> This is my JSP page. <h1 style="color:red">用户名：rapido, 密码：liying5201314</h1> <br> </body> </html>
向Web站点发送GET请求，POST请求，并从Web站点取得相应数据示例
原文：http://blog.csdn.net/xiaokui_wingfly/article/details/46278895