J2EE自定义mvc【框架配置及功能】

女爷i 2024-03-17 14:25 45阅读 0赞

**目录**

一、配置步骤

二、配置框架前三步

导入相应的jar

导入相应的Class

导入xml文件

三、优化基本操作（增删改）

1、基础优化

编写实体类

编写BookDao类

优化BookDao

JUnit测试

2、后台优化

3、前端优化

--------------------

## 一、配置步骤 ##

1.  将框架打成jar包，然后导入新工程，并且把框架的依赖jar包导入进去
2.  将分页标签相关文件、及相关助手类导入
3.  框架的配置文件添加、以及web.xml的配置-以后开源框架的使用从这一步开始
4.  完成Book实体类及bookDao的编写
5.  完成通用的增删改方法
6.  完成BookAction
7.  完成mvc.xml的配置
8.  完成前台代码的编写

## 二、配置框架前三步 ##

### 导入相应的jar ###

![f14303ebadb24e87af2d2818b62fc0c0.png][]

> 导入之后我们选中所有的jar包===》右键===》Build Path===》Add to Build Path

![f28e63fa5d8a4a47b5ea3db6f8eaab81.png][]

### 导入相应的Class ###

![3710089d70f94c43b4e29d4e90ae38b4.png][]

### 导入xml文件 ###

<?xml version="1.0" encoding="UTF-8"?>
    <config>
    	<action path="/book" type="com.tgq.web.BookAction">
    		<forward name="list" path="/bookList.jsp" redirect="false" />
    		<forward name="toList" path="/book.action?methodName=list"
    			redirect="true" />
    		<forward name="toEdit" path="/bookEdit.jsp" redirect="false" />
    	</action>
    
    </config>

测试我们的数据库能否连接

![53fdd433b7684e8bb27dbb7da83db3f2.png][]

## 三、优化基本操作（增删改） ##

### 1、基础优化 ###

#### 编写实体类 ####

package com.tgq.entity;
    
    /**
     * 实体类
     * 
     * @author tgq
     *
     */
    public class Book {
    	private int bid;
    	private String bname;
    	private float price;
    
    	public int getBid() {
    		return bid;
    	}
    
    	public void setBid(int bid) {
    		this.bid = bid;
    	}
    
    	public String getBname() {
    		return bname;
    	}
    
    	public void setBname(String bname) {
    		this.bname = bname;
    	}
    
    	public float getPrice() {
    		return price;
    	}
    
    	public void setPrice(float price) {
    		this.price = price;
    	}
    
    	@Override
    	public String toString() {
    		return "Book [bid=" + bid + ", bname=" + bname + ", price=" + price + "]";
    	}
    
    	public Book(int bid, String bname, float price) {
    		super();
    		this.bid = bid;
    		this.bname = bname;
    		this.price = price;
    	}
    
    	public Book() {
    		// TODO Auto-generated constructor stub
    	}
    }

#### 编写BookDao类 ####

> 编写增删改查的方法

package com.tgq.dao;
    
    import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.util.List;
    
    import com.tgq.entity.Book;
    import com.tgq.util.BaseDao;
    import com.tgq.util.DBAccess;
    import com.tgq.util.PageBean;
    import com.tgq.util.StringUtils;
    
    public class BookDao extends BaseDao<Book> {
    
    	public List<Book> list(Book book, PageBean pageBean) throws Exception {
    		String sql = "select * from t_mvc_book where 1=1 ";
    		String bname = book.getBname();
    		int bid = book.getBid();
    		// 判断是否为空
    		if (StringUtils.isNotBlank(bname)) {
    			sql += " and bname like '%" + bname + "%'";
    		}
    		// 判断前台是否传bid
    		if (bid != 0) {
    			sql += " and bid=" + bid;
    		}
    
    		return super.executeQuery(sql, Book.class, pageBean);
    	}
    
    	/**
    	 * 增加Book的方法
    	 * 
    	 * @param book
    	 *            实体类
    	 * @return
    	 * @throws Exception
    	 *             万能异常
    	 */
    	public int addBook(Book book) throws Exception {
    		String sql = "insert into t_mvc_book values(?,?,?)";
    		Connection conn = DBAccess.getConnection();
    		PreparedStatement ps = conn.prepareStatement(sql);
    		ps.setObject(1, book.getBid());
    		ps.setObject(2, book.getBname());
    		ps.setObject(3, book.getPrice());
    
    		return ps.executeUpdate();
    
    	}
    
    	/**
    	 * 删除Book的方法 ，根据id删除
    	 * 
    	 * @param book
    	 *            实体类
    	 * @return
    	 * @throws Exception
    	 *             万能异常
    	 */
    	public int delBook(Book book) throws Exception {
    		String sql = "delete from t_mvc_book where bid=?";
    		Connection conn = DBAccess.getConnection();
    		PreparedStatement ps = conn.prepareStatement(sql);
    		ps.setObject(1, book.getBid());
    
    		return ps.executeUpdate();
    
    	}
    
    	/**
    	 * 修改Book的方法
    	 * 
    	 * @param book
    	 *            实体类
    	 * @return
    	 * @throws Exception
    	 *             万能异常
    	 */
    	public int updateBook(Book book) throws Exception {
    		String sql = "update t_mvc_book set bname=?,price=? where bid=?";
    		Connection conn = DBAccess.getConnection();
    		PreparedStatement ps = conn.prepareStatement(sql);
    		ps.setObject(1, book.getBname());
    		ps.setObject(2, book.getPrice());
    		ps.setObject(3, book.getBid());
    
    		return ps.executeUpdate();
    
    	}
    
    }

> 1、在增删改的方法里面我们这两行代码是一样的、重复的
> 
>     Connection conn = DBAccess.getConnection();
>     		PreparedStatement ps = conn.prepareStatement(sql);
> 
> 2、代码逻辑是重复的===》sql占位符赋值
> 
>     ps.setObject(1, book.getBid());
>     		ps.setObject(2, book.getBname());
>     		ps.setObject(3, book.getPrice());
> 
> **怎么解决？BaseDao**  
> 进行一个通用的增删改的方法
> 
>     /**
>     	 * 通用的增删改方法
>     	 * 
>     	 * @param sql
>     	 *            数据库sql语句
>     	 * @param t
>     	 *            对应表的实体类
>     	 * @param attrs
>     	 *            要修改的属性值
>     	 * @return
>     	 * @throws Exception
>     	 *             万能异常
>     	 */
>     	public int executeUpdate(String sql, T t, String[] attrs) throws Exception {
>     		Connection conn = DBAccess.getConnection();
>     		PreparedStatement ps = conn.prepareStatement(sql);
>     		//利用fori 下标来进行？的赋值
>     		for (int i = 0; i < attrs.length; i++) {
>     			Field field = t.getClass().getDeclaredField(attrs[i]);
>     			// 打开权限
>     			field.setAccessible(true);
>     			
>     			ps.setObject(i + 1, field.get(t));
>     
>     		}
>     
>     		return ps.executeUpdate();
>     	}
> 
>   
>

#### 优化BookDao ####

> 我们在BaseDao类里面增加了一个通用的增删改的方法，我们在**BookDao**里面利用起来

/**
    	 * 增加Book的方法
    	 * 
    	 * @param book
    	 *            实体类
    	 * @return
    	 * @throws Exception
    	 *             万能异常
    	 */
    	public int addBook(Book book) throws Exception {
    		String sql = "insert into t_mvc_book values(?,?,?)";
    		return super.executeUpdate(sql, book, new String[] { "bid", "bname", "price" });
    	}
    
    	/**
    	 * 删除Book的方法 ，根据id删除
    	 * 
    	 * @param book
    	 *            实体类
    	 * @return
    	 * @throws Exception
    	 *             万能异常
    	 */
    	public int delBook(Book book) throws Exception {
    		String sql = "delete from t_mvc_book where bid=?";
    		return super.executeUpdate(sql, book, new String[] { "bid" });
    
    	}
    
    	/**
    	 * 修改Book的方法
    	 * 
    	 * @param book
    	 *            实体类
    	 * @return
    	 * @throws Exception
    	 *             万能异常
    	 */
    	public int updateBook(Book book) throws Exception {
    		String sql = "update t_mvc_book set bname=?,price=? where bid=?";
    		return super.executeUpdate(sql, book, new String[] { "bname", "price", "bid" });
    
    	}

#### JUnit测试 ####

> 选中我们的类名===》ctrl+N===》JUnit Test Case===》选中顶部的New JUnit 4 test===》Next

![eedb7036b11c41a58d12e5d23d1be922.png][]

> 勾选BookDao===》Finish

![523b6625b1e5415fb358c85ec21396ee.png][]

> BookDaoTest测试

package com.tgq.dao;
    
    import static org.junit.Assert.*;
    
    import java.util.List;
    
    import org.junit.Test;
    
    import com.tgq.entity.Book;
    import com.tgq.util.PageBean;
    
    public class BookDaoTest {
    
    	private BookDao bookDao = new BookDao();
    
    	@Test
    	public void testList() throws Exception {
    		Book book = new Book();
    		book.setBname("52");
    		PageBean pageBean = new PageBean();
    		// pageBean.setPage(2);
    		List<Book> list = bookDao.list(book, pageBean);
    		for (Book b : list) {
    			System.out.println(b);
    		}
    
    	}
    
    	@Test
    	public void testAddBook() throws Exception {
    		Book book = new Book();
    		book.setBid(52);
    		book.setBname("5252");
    		book.setPrice(12f);
    		bookDao.addBook(book);
    	}
    
    	@Test
    	public void testDelBook() throws Exception {
    		Book book = new Book();
    		book.setBid(52);
    		bookDao.delBook(book);
    	}
    
    	@Test
    	public void testUpdateBook() throws Exception {
    		Book book = new Book();
    		book.setBid(52);
    		book.setBname("5252");
    		book.setPrice(19f);
    		bookDao.updateBook(book);
    	}
    
    }

测试结果：

![d45968f043b646feb5d9ccea9019050f.png][]

### 2、后台优化 ###

> 我们新建一个web包，在里面新建一个BookAction类（**class**），继承**ActionSupport**，实现
> 
> **ModelDriver**接口，编写

![555bc902e22a4beb94382c7c67d51a22.png][]

package com.tgq.web;
    
    import java.util.List;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import com.tgq.dao.BookDao;
    import com.tgq.entity.Book;
    import com.tgq.util.PageBean;
    import com.zking.framework.ActionSupport;
    import com.zking.framework.ModelDriver;
    
    public class BookAction extends ActionSupport implements ModelDriver<Book> {
    
    	private Book book = new Book();
    	private BookDao bookDao = new BookDao();
    
    	// 查询 bookList.jsp
    	public String list(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    
    		PageBean pageBean = new PageBean();
    
    		pageBean.setRequest(req);
    
    		List<Book> list = bookDao.list(book, pageBean);
    		req.setAttribute("list", list);
    		req.setAttribute("pageBean", pageBean);
    		return "list";
    	}
    
    	// 编辑界面跳转 bookEdit.jsp
    	public String toEdit(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    		// 前提
    		if (book.getBid() != 0) {
    			List<Book> list = bookDao.list(book, null);// 不需要分页
    			req.setAttribute("b", list.get(0));
    		}
    
    		return "toEdit";
    	}
    
    	// 增加 重定向到book.action?methodName=list
    	public String add(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    		bookDao.addBook(book);
    		return "toEdit";
    	}
    
    	// 删除
    	public String del(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    		bookDao.delBook(book);
    		return "toEdit";
    	}
    
    	// 修改
    	public String update(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    		bookDao.updateBook(book);
    		return "toEdit";
    	}
    
    	@Override
    	public Book getModel() {
    
    		return book;
    	}
    
    }

> 我们编写jsp界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    	pageEncoding="UTF-8"%>
    <%@ taglib uri="http://jsp.veryedu.cn" prefix="z"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    <!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">
    <link
    	href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
    	rel="stylesheet">
    <script
    	src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js"></script>
    <title>书籍列表</title>
    <style type="text/css">
    .page-item input {
    	padding: 0;
    	width: 40px;
    	height: 100%;
    	text-align: center;
    	margin: 0 6px;
    }
    
    .page-item input, .page-item b {
    	line-height: 38px;
    	float: left;
    	font-weight: 400;
    }
    
    .page-item.go-input {
    	margin: 0 10px;
    }
    </style>
    </head>
    <body>
    	<form class="form-inline"
    		action="${pageContext.request.contextPath }/book.action?methodName=list"
    		method="post">
    		<div class="form-group mb-2">
    			<input type="text" class="form-control-plaintext" name="bname"
    				placeholder="请输入书籍名称">
    			
    			
    			<input name="pagination" value="false" type="hidden">
    		</div>
    		<button type="submit" class="btn btn-primary mb-2">查询</button>
    		<a class="btn btn-primary mb-2"
    			href="${pageContext.request.contextPath }/book.action?methodName=toEdit">新增</a>
    	</form>
    
    	<table class="table table-striped">
    		<thead>
    			<tr>
    				<th scope="col">书籍ID</th>
    				<th scope="col">书籍名</th>
    				<th scope="col">价格</th>
    				<th scope="col">操作</th>
    			</tr>
    		</thead>
    		<tbody>
    			<c:forEach var="b" items="${books }">
    				<tr>
    					<td>${b.bid }</td>
    					<td>${b.bname }</td>
    					<td>${b.price }</td>
    					<td><a
    						href="${pageContext.request.contextPath }/book.action?methodName=toEdit&bid=${b.bid}">修改</a>
    						<a
    						href="${pageContext.request.contextPath }/book.action?methodName=delete&bid=${b.bid}">删除</a>
    					</td>
    				</tr>
    			</c:forEach>
    		</tbody>
    	</table>
    	
    	<z:page pageBean="${pageBean }"></z:page>
    
    </body>
    </html>

> 增加，修改的jsp界面。
> 
> 判断你点击的是否是增加还是修改
> 
>     action="${pageContext.request.contextPath }/book.action?methodName=${empty b ? 'add' : 'edit'}"

### 3、前端优化 ###

> 我们运行[书籍列表][Link 1]
> 
> 进行一个搜索，新增、修改、删除

![c94d355a63d94b87aedcb2508f3b828e.png][]

> 我们删除ID：16、22

![7510c59f241a488f9512aadbcb7a3a8a.png][]

> 新增一个
> 
> ID：12  
> 书籍名：圣墟12  
> 价格：123

![cc9b25b0d12c46beb603a2b6cc7e4055.png][]

> 修改ID：12  
> 书籍名：圣墟1234  
> 价格：12345

![598da7136ce1490f8af2963716c6809d.png][]

希望对你们有用！！！

[f14303ebadb24e87af2d2818b62fc0c0.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/90eb3b6ba31e48218424895304b2d051.png
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[3710089d70f94c43b4e29d4e90ae38b4.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/0a38f82d38c548139f8057660a8f499f.png
[53fdd433b7684e8bb27dbb7da83db3f2.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/ba50235702b64ba79c0a55db25a9efca.png
[eedb7036b11c41a58d12e5d23d1be922.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/69b894544f2e4ee4beb742356c760656.png
[523b6625b1e5415fb358c85ec21396ee.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/aa8e8b4b3b714957b5170a5e91b7f4fd.png
[d45968f043b646feb5d9ccea9019050f.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/0a8dfcd3de1548d89ef81de4574aaca6.png
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[Link 1]: http://localhost:8080/J2EE_mvc_crud/book.action?methodName=list
[c94d355a63d94b87aedcb2508f3b828e.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/29f5a969e9cf409aa3113520fc8d8475.png
[7510c59f241a488f9512aadbcb7a3a8a.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/52d577ef2ce14aaeb385339782e8a07d.png
[cc9b25b0d12c46beb603a2b6cc7e4055.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/8faa92ba5dc9400380f340ff10e0ab3f.png
[598da7136ce1490f8af2963716c6809d.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/6a30489fd07d4e0198336a652a7086d4.png