MVC框架基础练习
mvc框架：应用于桌面程序
Model模型：是应用程序的主体部分，主要包括业务逻辑模块（web项目中的service和dao类）和数据模块（vo类）模型与数据格式无关，这样一个模型能为多个视图提供数据，由于应用于模型的代码只需要写一次就可以被多个视图重用，所以减少了代码的重复行
view视图：用户与之交互的界面，在web项目中一般有jsp，html组成
controller控制器：接收来自界面的请求并交给模型，进行处理，在这个过程中控制器不做
任何处理，只是起到了一个连接的作用
优点：
1.低耦合性：视图层和业务层分离，很容易改变应用程序的数据层和业务规则
2.高重用性和可适用性，允许各种不同样式的视图来访问一个服务段的代码
3.较低的生命周期成本成本，mvc可降低开发和维护用户接口的技术含量
4.部署方便-
由MVC架构衍生出的三层架构
1.表现层：接收请求，封装数据，调用业务逻辑层，响应数据
2.业务逻辑层:对业务逻辑进行封装，组合数据持久层中基本功能，形成复杂的业务逻辑。
例如：注册业务，先查询是否存在，再进行添加
3.数据持久层：对数据库进行增删改查等基本操作
mvc基础模式练习
//register注册界面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
Insert title here
用户注册
<%if(request.getAttribute("mag")!=null){ %>
<%=request.getAttribute("mag") %>
<%} %>
//success.jsp文件，注册成功页面
<%@page import="demo.vo.Customer"%>
<%@page import="java.util.List"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
Insert title here
<%=request.getAttribute("mag") %>
<%List list=(List)request.getAttribute("list"); %>
<%if(list!=null&&list.size()!=0){ %>
id
name
age
account
<%for(Customer c:list){ %>
>
<%=c.getId() %>
<%=c.getName() %>
<%=c.getAge() %>
<%=c.getAccount() %>
<%} %>
<%} %>
//update修改界面
<%@page import="demo.vo.Customer"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
Insert title here
修改顾客信息
<%Customer c=(Customer)request.getAttribute("customer"); %>
//servlet表现层
//RegisterServlet
package demo.controller;
import java.io.IOException;
import java.util.List;
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 demo.service.CustomerService;
import demo.vo.Customer;
/**
* Servlet implementation class RegisterServlet
*/
@WebServlet("/RegisterServlet")
public class RegisterServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
CustomerService service=new CustomerService();
/**
* @see HttpServlet#HttpServlet()
*/
public RegisterServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String name=request.getParameter("name");
int age=Integer.parseInt(request.getParameter("age"));
String account= request.getParameter("account");
String pwd=request.getParameter("pwd");
Customer customer=new Customer(1,name,age,account,pwd);
if(service.register(customer)) {
// 注册成功，跳转到成功页面
request.setAttribute("mag","注册成功");
request.getRequestDispatcher("success.jsp").forward(request, response);
}else {
// 注册失败，跳回到注册页面，并显示账号以存在
request.setAttribute("mag", "账号已存在");
request.getRequestDispatcher("register.jsp").forward(request, response);
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
//ShowAllServlet
package demo.controller;
import java.io.IOException;
import java.util.List;
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 demo.dao.CustomerDao;
import demo.service.CustomerService;
import demo.vo.Customer;
/**
* Servlet implementation class ShowAllServlet
*/
@WebServlet("/ShowAllServlet")
public class ShowAllServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
CustomerService service=new CustomerService();
/**
* @see HttpServlet#HttpServlet()
*/
public ShowAllServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
List list=service.getAllCustomer();
request.setAttribute("list", list);
if(request.getAttribute("mag")!=null) {
request.setAttribute("mag", request.getAttribute("mag"));
}
request.getRequestDispatcher("success.jsp").forward(request, response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
//UpdateServlet
package demo.controller;
import java.io.IOException;
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 demo.service.CustomerService;
import demo.vo.Customer;
/**
* Servlet implementation class UpdateServlet
*/
@WebServlet("/UpdateServlet")
public class UpdateServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
CustomerService service=new CustomerService();
/**
* @see HttpServlet#HttpServlet()
*/
public UpdateServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//获取要修改的顾客id
int id=Integer.parseInt(request.getParameter("id"));
// 现将顾客的信息获取，传递到页面中，作为默认数据进行修改
// 根据id查询顾客对象业务
Customer customer=service.getCustomerById(id);
request.setAttribute("customer", customer);
request.getRequestDispatcher("update.jsp").forward(request, response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
//Update01Servlet
package demo.controller;
import java.io.IOException;
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 demo.service.CustomerService;
import demo.vo.Customer;
/**
* Servlet implementation class Update01Servlet
*/
@WebServlet("/Update01Servlet")
public class Update01Servlet extends HttpServlet {
private static final long serialVersionUID = 1L;
CustomerService service=new CustomerService();
/**
* @see HttpServlet#HttpServlet()
*/
public Update01Servlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
int id=0;
int age=0;
// 先判断id和age是否能够进行数字转换
if(request.getParameter("id")!=null&&request.getParameter("age")!=null
&& !"".equals(request.getParameter("age"))) {
id=Integer.parseInt(request.getParameter("id"));
age=Integer.parseInt(request.getParameter("age"));
}
String name=request.getParameter("name");
String account=request.getParameter("account");
String pwd=request.getParameter("pwd");
// 再判断字符串属性不是空串
if(!"".equals(name)&&!"".equals(pwd)&&!"".equals(account)) {
Customer c=new Customer(id,name,age,account,pwd);
// 调用修改业务
if(service.updateCustomer(c)) {
request.setAttribute("mag", "修改成功");
}else {
request.setAttribute("mag", "修改失败");
}
}else {
request.setAttribute("mag", "修改失败");
}
request.getRequestDispatcher("ShowAllServlet").forward(request, response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
//DeleteServlet
package demo.controller;
import java.io.IOException;
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 demo.service.CustomerService;
/**
* Servlet implementation class DeleteServlet
*/
@WebServlet("/DeleteServlet")
public class DeleteServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
CustomerService service=new CustomerService();
/**
* @see HttpServlet#HttpServlet()
*/
public DeleteServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
int id=Integer.parseInt(request.getParameter("id"));
if(service.deleteCustomerById(id)) {
request.setAttribute("mag", "删除成功");
}else {
request.setAttribute("mag", "删除失败");
}
request.getRequestDispatcher("ShowAllServlet").forward(request, response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
//DeleteServlet01
package demo.controller;
import java.io.IOException;
import java.util.List;
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 demo.service.CustomerService;
/**
* Servlet implementation class DeleteServlet01
*/
@WebServlet("/DeleteServlet01")
public class DeleteServlet01 extends HttpServlet {
private static final long serialVersionUID = 1L;
CustomerService service=new CustomerService();
/**
* @see HttpServlet#HttpServlet()
*/
public DeleteServlet01() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String[] str=request.getParameterValues("san");
int[] in=new int[str.length];
if(str.length!=0) {
for(int i=0;i getAllCustomer(){
return dao.getCustomer();
}
// 修改业务
public boolean updateCustomer(Customer customer) {
return dao.updateCustomer(customer);
}
// 删除业务
public boolean deleteCustomerById(int id) {
return dao.deleteCustomerById(id);
}
}
//数据持久层dao
package demo.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import demo.common.DBUtils;
import demo.vo.Customer;
public class CustomerDao {
//查询注册的账号是否重复
public boolean selectCustomerByAccount(String account) {
// 1加载驱动2.获得连接3.执行sql语句处理4.关闭资源
Connection conn=DBUtils.getConn();
String sql="select account from customer where account=?";
PreparedStatement ps=null;
ResultSet rs=null;
try {
ps=conn.prepareStatement(sql);
ps.setString(1, account);
rs=ps.executeQuery();
if(rs.next()) {
return true;
}
return false;
}catch(Exception e) {
e.printStackTrace();
return false;
}finally {
DBUtils.close(conn, ps, rs);
}
}
// 插入注册的数据
public boolean insertCustomer(Customer customer) {
Connection conn =DBUtils.getConn();
PreparedStatement ps=null;
String sql="insert into customer values(null,?,?,?,?)";
try {
ps=conn.prepareStatement(sql);
ps.setString(1,customer.getName());
ps.setInt(2, customer.getAge());
ps.setString(3,customer.getAccount());
ps.setString(4,customer.getPwd());
if(ps.executeUpdate()>0) {
return true;
}
return false;
}catch(Exception e) {
e.printStackTrace();
return false;
}finally {
DBUtils.close(conn, ps, null);
}
}
// 一览数据
public List getCustomer() {
Connection conn =DBUtils.getConn();
PreparedStatement ps=null;
ResultSet rs=null;
List list=new ArrayList();
String sql="select* from customer";
try {
ps=conn.prepareStatement(sql);
rs=ps.executeQuery();
while(rs.next()) {
int id=rs.getInt(1);
String name=rs.getString(2);
int age=rs.getInt(3);
String account=rs.getString(4);
String pwd=rs.getString(5);
Customer customer=new Customer(id,name,age,account,pwd);
list.add(customer);
}
return list;
}catch(Exception e) {
e.printStackTrace();
return null;
}finally {
DBUtils.close(conn, ps, rs);
}
}
// 根据id查询Customer
public Customer getCustomerById(int id) {
Connection conn=DBUtils.getConn();
PreparedStatement ps=null;
ResultSet rs=null;
String sql="select *from customer where id=?";
try {
ps=conn.prepareStatement(sql);
ps.setInt(1, id);
rs=ps.executeQuery();
if(rs.next()) {
Customer customer=new Customer(rs.getInt("id"),
rs.getString("name"),rs.getInt("age"),rs.getString(4),rs.getString(5));
return customer;
}
return null;
} catch (Exception e) {
// TODO: handle exception
return null;
}finally {
DBUtils.close(conn, ps, rs);
}
}
public boolean updateCustomer(Customer customer) {
Connection conn=DBUtils.getConn();
PreparedStatement ps=null;
String sql="update customer set name=?,age=?,account=?,pwd=? where id=? ";
try {
ps=conn.prepareStatement(sql);
ps.setString(1, customer.getName());
ps.setInt(2, customer.getAge());
ps.setString(3, customer.getAccount());
ps.setString(4, customer.getPwd());
ps.setInt(5, customer.getId());
if(ps.executeUpdate()>0) {
return true;
}
return false;
}catch (Exception e) {
e.printStackTrace();
return false;
}
finally {
DBUtils.close(conn, ps, null);
}
}
// 删除
public boolean deleteCustomerById(int id) {
Connection conn=DBUtils.getConn();
PreparedStatement ps=null;
String sql="delete from customer where id=?";
try {
ps=conn.prepareStatement(sql);
ps.setInt(1, id);
if(ps.executeUpdate()>0) {
return true;
}
return false;
}catch (Exception e) {
e.printStackTrace();
return false;
}
finally {
DBUtils.close(conn, ps, null);
}
}
}
//数据库连接封装
package demo.common;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
public class DBUtils {
// 获取Connection对象(数据库连接相关数据可通过参数控制)
public static Connection getConn(String driver,String url,String user,String pwd) {
try {
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,user,pwd);
return conn;
}catch(Exception e) {
return null;
}
}
// 固定数据库连接参数获取Connection对象
public static Connection getConn() {
try {
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/mysql2209?useUnicode=true&characterEncoding=utf8",
"root",
"root"
);
return conn;
}catch(Exception e) {
return null;
}
}
// 关流
public static void close(Connection conn,PreparedStatement ps,ResultSet rs) {
try {
if(rs!=null)rs.close();
if(ps!=null)ps.close();
if(conn!=null)conn.close();
}catch(Exception e) {
}
}
}
//.vo类对象
package demo.vo;
public class Customer {
private int id;
private String name;
private int age;
private String account;
private String pwd;
public Customer() {}
public Customer(int id, String name, int age, String account, String pwd) {
super();
this.id = id;
this.name = name;
this.age = age;
this.account = account;
this.pwd = pwd;
}
@Override
public String toString() {
return "Customer [id=" + id + ", name=" + name + ", age=" + age + ", account=" + account + ", pwd=" + pwd + "]";
}
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getAccount() {
return account;
}
public void setAccount(String account) {
this.account = account;
}
public String getPwd() {
return pwd;
}
public void setPwd(String pwd) {
this.pwd = pwd;
}
}