一 实体类
package
com.po;
//用户类
public
class
Users {
private
String
username
;
private
String
password
;
public
Users()
{
}
public
String getUsername() {
return
username
;
}
public
void
setUsername(String username) {
this
.
username
= username;
}
public
String getPassword() {
return
password
;
}
public
void
setPassword(String password) {
this
.
password
= password;
}
}
二 Servlet类
package servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.po.Users;
public class LoginServlet extends HttpServlet {
/**
* Constructor of the object.
*/
public LoginServlet() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Users u = new Users();
String username = request.getParameter("username");
String password = request.getParameter("password");
u.setUsername(username);
u.setPassword(password);
//判断用户名和密码是否合法
if(u.getUsername().equals("admin")&&u.getPassword().equals("admin"))
{
response.sendRedirect(request.getContextPath()+"/login_success.jsp");
}
else
{
response.sendRedirect(request.getContextPath()+"/login_failure.jsp");
}
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
三 界面
1 login.jsp
<%@
page
language
=
"java"
import
=
"java.util.*"
contentType
=
"text/html; charset=utf-8"
%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+
"://"
+request.getServerName()+
":"
+request.getServerPort()+path+
"/"
;
%>
<
html
>
<
head
>
<!-- Page title -->
<
title
>
imooc
- Login
</
title
>
<!-- End of Page title -->
<!-- Libraries -->
<
link
type
=
"text/css"
href
=
"css/login.css"
rel
=
"stylesheet"
/>
<
link
type
=
"text/css"
href
=
"css/smoothness/jquery-ui-1.7.2.custom.html"
rel
=
"stylesheet"
/>
<
script
type
=
"text/javascript"
src
=
"js/jquery-1.3.2.min.js"
></
script
>
<
script
type
=
"text/javascript"
src
=
"js/easyTooltip.js"
></
script
>
<
script
type
=
"text/javascript"
src
=
"js/jquery-ui-1.7.2.custom.min.js"
></
script
>
<!-- End of Libraries -->
</
head
>
<
body
>
<
div
id
=
"container"
>
<
div
class
=
"logo"
>
<
a
href
=
"#"
><
img
src
=
"assets/logo.png"
alt
=
""
/></
a
>
</
div
>
<
div
id
=
"box"
>
<
form
action
=
"servlet/LoginServlet"
method
=
"post"
>
<
p
class
=
"main"
>
<
label
>
用户名:
</
label
>
<
input
name
=
"username"
value
=
""
/>
<
label
>
密码:
</
label
>
<
input
type
=
"password"
name
=
"password"
value
=
""
>
</
p
>
<
p
class
=
"space"
>
<
input
type
=
"submit"
value
=
"登录"
class
=
"login"
style
="
cursor
:
pointer
;"
/>
</
p
>
</
form
>
</
div
>
</
div
>
</
body
>
</
html
>
2 login_success.jsp
<%@
page
language
=
"java"
import
=
"java.util.*"
contentType
=
"text/html; charset=utf-8"
%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+
"://"
+request.getServerName()+
":"
+request.getServerPort()+path+
"/"
;
%>
<
html
>
<
head
>
<!-- Page title -->
<
title
>
imooc
- Login
</
title
>
<!-- End of Page title -->
<!-- Libraries -->
<
link
type
=
"text/css"
href
=
"css/login.css"
rel
=
"stylesheet"
/>
<
link
type
=
"text/css"
href
=
"css/smoothness/jquery-ui-1.7.2.custom.html"
rel
=
"stylesheet"
/>
<
script
type
=
"text/javascript"
src
=
"js/jquery-1.3.2.min.js"
></
script
>
<
script
type
=
"text/javascript"
src
=
"js/easyTooltip.js"
></
script
>
<
script
type
=
"text/javascript"
src
=
"js/jquery-ui-1.7.2.custom.min.js"
></
script
>
<!-- End of Libraries -->
</
head
>
<
body
>
<
div
id
=
"container"
>
<
div
class
=
"logo"
>
<
a
href
=
"#"
><
img
src
=
"assets/logo.png"
alt
=
""
/></
a
>
</
div
>
<
div
id
=
"box"
>
<%
String loginUser =
""
;
if
(session.getAttribute(
"loginUser"
)!=
null
)
{
loginUser = session.getAttribute(
"loginUser"
).toString();
}
%>
欢迎您
<
font
color
=
"red"
>
<%=
loginUser
%>
</
font
>
,登录成功!
</
div
>
</
div
>
</
body
>
</
html
>
3 login_failure.jsp
<%@
page
language
=
"java"
import
=
"java.util.*"
contentType
=
"text/html; charset=utf-8"
%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+
"://"
+request.getServerName()+
":"
+request.getServerPort()+path+
"/"
;
%>
<
html
>
<
head
>
<!-- Page title -->
<
title
>
imooc
- Login
</
title
>
<!-- End of Page title -->
<!-- Libraries -->
<
link
type
=
"text/css"
href
=
"css/login.css"
rel
=
"stylesheet"
/>
<
link
type
=
"text/css"
href
=
"css/smoothness/jquery-ui-1.7.2.custom.html"
rel
=
"stylesheet"
/>
<
script
type
=
"text/javascript"
src
=
"js/jquery-1.3.2.min.js"
></
script
>
<
script
type
=
"text/javascript"
src
=
"js/easyTooltip.js"
></
script
>
<
script
type
=
"text/javascript"
src
=
"js/jquery-ui-1.7.2.custom.min.js"
></
script
>
<!-- End of Libraries -->
</
head
>
<
body
>
<
div
id
=
"container"
>
<
div
class
=
"logo"
>
<
a
href
=
"#"
><
img
src
=
"assets/logo.png"
alt
=
""
/></
a
>
</
div
>
<
div
id
=
"box"
>
登录失败!请检查用户或者密码!
<
br
>
<
a
href
=
"login.jsp"
>
返回登录
</
a
>
</
div
>
</
div
>
</
body
>
</
html
>
四 测试