J2EE自定义mvc【框架配置及功能】-Toy模板网

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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

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
将分页标签相关文件、及相关助手类导入
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
完成Book实体类及bookDao的编写
完成通用的增删改方法
完成BookAction
完成mvc.xml的配置
完成前台代码的编写

二、配置框架前三步

导入相应的jar

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

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

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

导入相应的Class

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

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

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

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

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

勾选BookDao===》Finish

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

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：

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

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

J2EE自定义mvc【框架配置及功能】,java-ee,mvc,java

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="${pageContext.request.contextPath }/book.action?methodName=list"
		method="post">
		<div class="form-group mb-2">
			<input type="text" class="form-control-plaintext" name="bname"
				placeholder="请输入书籍名称">
			<!-- 			<input name="rows" value="20" type="hidden"> -->
			<!-- 不想分页 -->
			<input name="pagination" value="false" type="hidden">
		</div>
		<button type="submit" class="btn btn-primary mb-2">查询</button>
		<a class="btn btn-primary mb-2"
			href="${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>
	<!-- 这一行代码就相当于前面分页需求前端的几十行了 -->
	<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'}"

<%@ 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>书籍新增/修改</title>
</head>
<body>
	<form class="form-inline"
		action="${pageContext.request.contextPath }/book.action?methodName=${empty b ? 'add' : 'edit'}" method="post">
		书籍ID：<input type="text" name="bid" value="${b.bid }"><br>
		书籍名称：<input type="text" name="bname" value="${b.bname }"><br>
		书籍价格：<input type="text" name="price" value="${b.price }"><br>
		<input type="submit">
	</form>


</body>
</html>