Java之MVC模式实现注册登录功能
文章目录
- 一、描述
- 源码结构图
- 二、需要的jar包
- 三、分层源码
- 3.1 bean下的Users类，代码入下
- 3.2 DAO层里面的接口类、实现类，代码如下
- 接口类代码如下
- 实现类代码如下：
- 3.3 framework框架下有Action接口，和该接口的实现类
- Action接口类代码如下
- Action实现类Login登录实现类
- Action实现类register登录实现类
- 实现Action的servlet
- 3.4 controller层控制的源码
- Login的servlet源码如下：
- Register的servlet源码如下：
- 3.5 web.xml配置文件
一、描述
Servlet+JSP+JavaBean模式(MVC)适合开发复杂的web应用，在这种模式下，servlet负责处理用户请求，jsp负责数据显示，javabean负责封装数据。 Servlet+JSP+JavaBean模式程序各个模块之间层次清晰，web开发推荐采用此种模式。
这里以一个最常用的用户登录注册程序来讲解Servlet+JSP+JavaBean开发模式，通过这个用户登录注册程序综合案例，把之前的学过的XML、Xpath、Servlet、jsp的知识点都串联起来。
源码结构图
二、需要的jar包
dom4j-1.6.1.jar dom4j用于操作XML文件
jaxen-1.1-beta-6.jar 用于解析XPath表达式
commons-beanutils-1.8.0.jar 工具类，用于处理bean对象
commons-logging.jar commons-beanutils-1.8.0.jar的依赖jar包
jstl.jar jstl标签库和EL表达式依赖包
standard.jar jstl标签库和EL表达式依赖包
三、分层源码
3.1 bean下的Users类，代码入下
package com.bean;
/**
* @Author: pomelo
* @Create: 2020-03-25 12:15
* @ProjectName: MVC
* @Package: com.bean
* @ClassName: Users
* @Description: 用户实体类
* @Version: 1.0
*/
public class Users {
private int id;
private String name;
private String password;
private String tel;
public Users(){};
public Users(String name, String password) {
this.name = name;
this.password = password;
}
public Users(String name, String password, String tel) {
this.name = name;
this.password = password;
this.tel = tel;
}
public Users(int id, String name, String password, String tel) {
this.id = id;
this.name = name;
this.password = password;
this.tel = tel;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getTel() {
return tel;
}
public void setTel(String tel) {
this.tel = tel;
}
}
3.2 DAO层里面的接口类、实现类，代码如下
接口类代码如下
public interface UserDao {
//注册用户
int userInfoAdd(Users user);
//用户登录
Users getUserBypwd(String name, String password);
}
实现类代码如下：
package com.dao.impl;
import com.bean.Users;
import com.dao.UserDao;
import com.util.ConnectionSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
/**
* @Author: pomelo
* @Create: 2020-03-25 12:20
* @ProjectName: MVC
* @Package: com.dao.impl
* @ClassName: UserDaoImpl
* @Description:
* @Version: 1.0
*/
public class UserDaoImpl implements UserDao {
@Override
public int userInfoAdd(Users user) {
PreparedStatement pState = null;
Connection conn = null;
int num = 0;
try {
conn = ConnectionSource.getConnection();
String sql = "insert into username (name,password,tel) values(?,?,?)";
pState = conn.prepareStatement(sql);
pState.setString(1,user.getName());
pState.setString(2,user.getPassword());
pState.setString(3,user.getTel());
num = pState.executeUpdate();
if (num == 1){
System.out.println("添加成功");
}else {
System.out.println("添加失败");
}
} catch (SQLException e) {
e.printStackTrace();
}finally {
ConnectionSource.closeAll(conn,pState);
}
return num;
}
@Override
public Users getUserBypwd(String name, String password) {
Connection conn = null;
PreparedStatement pState = null;
ResultSet res = null;
Users user = null;
try {
conn = ConnectionSource.getConnection();
String sql = "select * from username where name = ? and password = ?";
pState = conn.prepareStatement(sql);
pState.setString(1,name);
pState.setString(2,password);
res = pState.executeQuery();
} catch (SQLException e) {
e.printStackTrace();
}finally {
ConnectionSource.closeAll(conn,pState,res);
}
return user;
}
}
3.3 framework框架下有Action接口，和该接口的实现类
Action接口类代码如下
public interface Action {
public String execute(HttpServletRequest request, HttpServletResponse response) throws Exception;
}
Action实现类Login登录实现类
package com.action;
import com.bean.Users;
import com.dao.UserDao;
import com.dao.impl.UserDaoImpl;
import framework.Action;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* @Author: pomelo
* @Create: 2020-03-25 14:26
* @ProjectName: mvctext
* @Package: com.action
* @ClassName: LoginAction
* @Description:
* @Version: 1.0
*/
public class LoginAction implements Action {
@Override
public String execute(HttpServletRequest request, HttpServletResponse response) throws Exception {
//获取参数
String name = request.getParameter("name");
String password = request.getParameter("password");
String tel = request.getParameter("tel");
UserDao userDao = new UserDaoImpl();
Users users = userDao.getUserBypwd(name,password);
if (users != null){
return "success.jsp";
}else{
return "login.jsp";
}
}
}
Action实现类register登录实现类
package com.action;
import com.bean.Users;
import com.dao.UserDao;
import com.dao.impl.UserDaoImpl;
import framework.Action;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* @Author: pomelo
* @Create: 2020-03-25 14:26
* @ProjectName: mvctext
* @Package: com.action
* @ClassName: RegisterAction
* @Description:
* @Version: 1.0
*/
public class RegisterAction implements Action {
@Override
public String execute(HttpServletRequest request, HttpServletResponse response) throws Exception {
//获取参数
String name = request.getParameter("name");
String password = request.getParameter("password");
String tel = request.getParameter("tel");
Users users = new Users();
users.setName(name);
users.setPassword(password);
users.setTel(tel);
UserDao userDao = new UserDaoImpl();
int num = userDao.userInfoAdd(users);
if (num == 1) {
return "login.jsp";
//response.setHeader("refresh","3;url=login.jsp");
//response.sendRedirect("shangcheng/index.jsp");
} else {
//response.setHeader("refresh","3;url=register.jsp");
return "register.jsp";
}
}
}
实现Action的servlet
package framework;
import com.action.LoginAction;
import com.action.RegisterAction;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* @Author: pomelo
* @Create: 2020-03-25 14:09
* @ProjectName: mvctext
* @Package: ${PACKAGE_NAME}
* @ClassName: ${NAME}
* @Description: ${description}
* @Version: 1.0
*/
@WebServlet(name = "ActionServlet")
public class ActionServlet extends HttpServlet{
private static final long serialVersionUID = 1L;
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request,response);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
// 设置编码集
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
Action action = getAction(request);
String result = action.execute(request, response);
//转发 根据返回字符串跳转页面
request.getRequestDispatcher(result).forward(request, response);
} catch (Exception e) {
response.sendError(500,"出错");
e.printStackTrace();
}
}
public Action getAction(HttpServletRequest request){
Action action = null;
//获取请求的uri = /mvc/login.action
String uri = request.getRequestURI();
//获取上下文路径以后的部分 /mvc
String contextPath = request.getContextPath();
//截取上下文路径以后的部分
String actionPath = uri.substring(contextPath.length());
//获取Action名称 trim()去除前后空格 /login.action
String actionName = actionPath.substring(1,actionPath.lastIndexOf(".")).trim(); //
// login register
if("login".equals(actionName)){
//执行登陆
action = new LoginAction();
}else if("register".equals(actionName)){
//执行注册
action = new RegisterAction();
}
return action;
}
}
3.4 controller层控制的源码
Login的servlet源码如下：
package com.controller;
import com.bean.Users;
import com.dao.UserDao;
import com.dao.impl.UserDaoImpl;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* @Author: pomelo
* @Create: 2020-03-25 12:34
* @ProjectName: MVC
* @Package: ${PACKAGE_NAME}
* @ClassName: ${NAME}
* @Description: ${description}
* @Version: 1.0
*/
@WebServlet(name = "Login")
public class Login extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
//获取参数
String name = request.getParameter("name");
String password = request.getParameter("password");
String tel = request.getParameter("tel");
UserDao userDao = new UserDaoImpl();
Users users = userDao.getUserBypwd(name,password);
if (users != null){
response.sendRedirect("success.jsp");
}else{
response.sendRedirect("login.jsp");
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request,response);
}
}
Register的servlet源码如下：
package com.controller;
import com.bean.Users;
import com.dao.UserDao;
import com.dao.impl.UserDaoImpl;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* @Author: pomelo
* @Create: 2020-03-25 12:35
* @ProjectName: MVC
* @Package: ${PACKAGE_NAME}
* @ClassName: ${NAME}
* @Description: ${description}
* @Version: 1.0
*/
@WebServlet(name = "Register")
public class Register extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
//获取参数
String name = request.getParameter("name");
String password = request.getParameter("pwd");
String tel = request.getParameter("tel");
Users users = new Users();
users.setName(name);
users.setPassword(password);
users.setTel(tel);
UserDao userDao = new UserDaoImpl();
int num = userDao.userInfoAdd(users);
if (num == 1){
response.setHeader("refresh","3;url=login.jsp");
//response.sendRedirect("shangcheng/index.jsp");
}else{
response.setHeader("refresh","3;url=register.jsp");
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request,response);
}
}
3.5 web.xml配置文件
<servlet>
<servlet-name>ActionServlet</servlet-name>
<servlet-class>framework.ActionServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ActionServlet</servlet-name>
<url-pattern>*.action</url-pattern>
</servlet-mapping>