使用HttpURLConnection类（利用sessionId保持会话)

TestServlet.java

1. package nj.servlet;
2. import javax.servlet.http.HttpServlet;
3. import javax.servlet.http.HttpServletRequest;
4. import javax.servlet.http.HttpServletResponse;
5. import javax.servlet.http.HttpSession;
6. public class TestServlet extends HttpServlet {
7.     public void doPost(HttpServletRequest request,HttpServletResponse response){
8.         HttpSession session=request.getSession();
9.         String str=(String)session.getAttribute("name");
10.         System.out.println("name:"+str);
11.         session.setAttribute("name", "nj");
12.         /*String ss=request.getHeader("Cookie");
13.         System.out.println("session id:"+ss);*/
14.     }
15.     public void doGet(HttpServletRequest request,HttpServletResponse response){
16.         this.doPost(request, response);
17.     }
18. }

 

TestServlet.java

1. package nj.ws.test;
2. import java.io.IOException;
3. import java.io.InputStream;
4. import java.io.OutputStream;
5. import java.net.HttpURLConnection;
6. import java.net.URL;
7. import java.util.List;
8. import java.util.Map;
9. import java.util.Set;
10. public class TestConnection {
11.     
12.     public static void main(String[] args){
13.         //第一次连接，返回session id
14.         String sessionId=testUrlConnection();
15.         //第二次使用session id连接
16.         connectionBySession(sessionId);
17.     }
18.     
19.     public static String testUrlConnection(){
20.         String urlStr="Http://localhost:8080/WebServiceProject/testServlet";
21.         OutputStream out=null;
22.         InputStream in=null;
23.         try {
24.             URL url=new URL(urlStr);
25.             HttpURLConnection con=(HttpURLConnection)url.openConnection();
26.             con.setRequestMethod("POST");
27.             
28.             //打印请求头信息
29.             Map hfs=con.getHeaderFields();
30.             Set<String> keys=hfs.keySet();
31.             for(String str:keys){
32.                 List<String> vs=(List)hfs.get(str);
33.                 System.out.print(str+":");
34.                 for(String v:vs){
35.                     System.out.print(v+"\t");
36.                 }
37.                 System.out.println();
38.             }
39.             System.out.println("-----------------------");
40.             String cookieValue=con.getHeaderField("Set-Cookie");
41.             System.out.println("cookie value:"+cookieValue);
42.             String sessionId=cookieValue.substring(0, cookieValue.indexOf(";"));
43.             return sessionId;
44.         } catch (Exception e) {
45.             e.printStackTrace();
46.             return null;
47.         }finally{
48.             try {
49.                 if(in!=null)
50.                     in.close();
51.                 if(out!=null)
52.                     out.close();
53.             } catch (IOException e) {
54.                 e.printStackTrace();
55.             }
56.         }
57.     }
58.     
59.     public static void connectionBySession(String sessionId){
60.         InputStream in=null;
61.         try{
62.             String url="Http://localhost:8080/WebServiceProject/testServlet";
63.             URL u=new URL(url);
64.             HttpURLConnection con=(HttpURLConnection)u.openConnection();
65.             con.setRequestMethod("POST");
66.             con.setRequestProperty("Cookie", sessionId);
67.             in=con.getInputStream();
68.         }catch(Exception e){
69.             e.printStackTrace();
70.         }finally{
71.             try {
72.                 if(in!=null)
73.                     in.close();
74.             } catch (IOException e) {
75.                 e.printStackTrace();
76.             }
77.         }
78.     }
79. }

运行后打印结果：

Web服务端：

name:null
name:nj

 

测试类打印：

null:HTTP/1.1 200 OK 
Content-Length:0 
Set-Cookie:JSESSIONID=7827696933343BC5005E5244369CB2A8; Path=/WebServiceProject 
Date:Mon, 01 Dec 2008 03:16:30 GMT 
Server:Apache-Coyote/1.1 
-----------------------
cookie value:JSESSIONID=7827696933343BC5005E5244369CB2A8; Path=/WebServiceProject