java web分层之——3层架构

3层架构，JSP+servlet+业务逻辑层

login.jsp

质保中心

用户名：

密码：

function ok(){

var username = document.getElementById("username").value;

var password = document.getElementById("password").value;

if(username == "" || password == ""){

// alert("用户名或密码不能为空！");

document.getElementById("tips").innerHTML="用户名或密码不能为空！";

}else{

document.loginForm.submit();

}

}

web.xml

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"

version="2.5">

DoLoginServlet

control.DoLoginServlet

DoLoginServlet

/doLogin

DoLoginServlet.java

package control;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import model.UserService;

public class DoLoginServlet extends HttpServlet {

private static final long serialVersionUID = 1L;

@Override

protected void service(HttpServletRequest request,

HttpServletResponse response) throws ServletException, IOException {

String encoding = "GBK";

request.setCharacterEncoding(encoding);

response.setCharacterEncoding(encoding);

String userName = request.getParameter("username");

String password = request.getParameter("password");

UserService s = new UserService();

boolean isLoginOk = s.login(userName, password);

if (isLoginOk) {

request.getRequestDispatcher("success.jsp").forward(request, response);

} else {

request.getRequestDispatcher("fail.jsp").forward(request, response);

}

}

}

业务逻辑层 UserService.java

package model;

public class UserService {

public boolean login(String username,String password) {

return ("黄启庆".equals(username) && "123456".equals(password));

}

}