jsp登录实例

来源：互联网发布：java 电商平台编辑：程序博客网时间：2024/04/30 02:07

刚开始从myeclipse项目转到eclipse运行，有错误提示
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;不能在项目中找到，
我了个去，javax库在哪里呢？我下了个myeclipse想解决它，下到的是注册版,安装时提示"out of date"
后来豪哥说添加apache tomcat v7.0库就可以了，我晕了，搞了那么久解决办法就在眼皮底下，怨念....，ok，下面是代码

//////////////////////////////////////////////////////////////////////////Hello.java
package cc.openhome;

import java.util.*;
public class Hello {
private Map<String, String> messages;
private Map<String, String> passmessages;

public Hello() {
messages = new HashMap<String, String>();
messages.put("caterpillar", "Hello");
messages.put("Justin", "Welcome");
messages.put("momor", "Hi");

passmessages = new HashMap<String, String>();
passmessages.put("caterpillar", "Hello");
passmessages.put("Justin", "Welcome");
passmessages.put("momor", "Hi");
passmessages.put("hong", "123");
}

public String doHello(String user) {
String message = messages.get(user);
return message + ", " + user + "!";
}

public String Check(String user, String password)
{
String pass=passmessages.get(user);
if(password.equals(pass))
return "登录成功";
else
return "sorry 登录失败";
}
}

/////////////////////////////////////////////////////////////HelloServlet.java
package cc.openhome;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloServlet extends HttpServlet {
private Hello hello;

public HelloServlet() {
hello = new Hello();
}

@Override
protected void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
String user = request.getParameter("user");
String password =request.getParameter("password");

//String message = hello.doHello(name);
// request.setAttribute("message", message);
// request.getRequestDispatcher("hello.jsp")
// .forward(request, response);


String mess=hello.Check(user, password);
request.setAttribute("message", mess);
request.getRequestDispatcher("show.jsp").forward(request, response);

}
}

////////////////////////////////////////////////////////login.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
</head>
<body>

<form method="get" action="hello.do">
用户名<input name="user"><br>密码    <input name="password" type="password"><br>
<br><input value="登录" type="submit"><br>

</body>
</html>

///////////////////////////////////////////////////////////////////////////show.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<html>
<head>
<meta http-equiv="Content-Type"
content="text/html; charset=UTF-8">
<title>${param.user}</title>
</head>
<body>
<h1>${message}</h1>
</body>
</html>

/////////////////////////////////////////////////////////web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>HelloServlet</servlet-name>
<servlet-class>cc.openhome.HelloServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HelloServlet</servlet-name>
<url-pattern>/hello.do</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>
30
</session-timeout>
</session-config>
<welcome-file-list>
<welcome-file>login.jsp</welcome-file>
</welcome-file-list>
</web-app>