本文直接展示servlet的测试结果。
servlet的代码中使用sendRedirect:
查看浏览器交互过程,先是请求该servlet:
Request URL:
http://localhost:8080/web/SessionTest
Request Method:
GET
Status Code:
302 Found
Request Headersview source
Accept:
text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Encoding:
gzip,deflate,sdch
Accept-Language:
en-US,en;q=0.8,zh;q=0.6,ko;q=0.4,ja;q=0.2
Cache-Control:
max-age=0
Connection:
keep-alive
Host:
localhost:8080
User-Agent:
Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.94 Safari/537.36
Response Headersview source
Content-Length:
Content-Type:
text/html;charset=UTF-8
Date:
Thu, 06 Jun 2013 07:16:55 GMT
Location:
http://localhost:8080/web/
Server:
Apache-Coyote/1.1
Set-Cookie:
JSESSIONID=8C8DCD7355CC62C75C9BD154B2ADEDD0; Path=/web/; HttpOnly
可以看到response返回了302,并带上了location, 指示浏览器做第二次跳转请求,浏览器得到提示后进行第二次请求。
同样的servlet,将代码改为forward,实现了在servlet容器内部的跳转,对浏览器实际上是不可见得。
看一下tomcat服务器的响应,一个200 OK之后,直接返回了内容,很直接
200 OK
Cookie:
JSESSIONID=4D4C34D45462707E53A475C060E2D2A2; test=test
DNT:
1
218
Thu, 06 Jun 2013 09:12:04 GMT
JSESSIONID=0FE64A4D2D1777BD44F08F2F8186384B; Path=/web/; HttpOnly
再看cookie的保存,将以上代码改为将cookie加入response:
再看HTTP head:
JSESSIONID=FB43328EF48C78B7122454F84B57F164
186
Thu, 06 Jun 2013 07:47:13 GMT
JSESSIONID=BC3FDA2D942F2F4B50757D9C436D21A9; Path=/web/; HttpOnly
test=test
Tomcat通过HTTP协议的Set-Cookie将servlet的cookie放入了响应头,查看浏览器的cookie,除了jsessionid,又加了一个test/test的cookie进来。
![](https://img.laitimes.com/img/_0nNw4CM6IyYiwiM6ICdiwiInBnaugDNllDOzUjN5YWO10yYwkjYtQGZlNTLykjZz0iMxUTMhVDMy8CX5IDM18CX1gDMw8CX05WZth2YhRHdh9CXkF2bsBXdvwVbvNmLllXZ0lmLywGZvw1LcpDc0RHaiojIsJye.jpg)