本期内容
?一、导入jar包
1、如何导出自己写出的MVC框架形成jar包？
①、在文件右键以下，找到Export...
?②、点击JAR file
③、寻找存放地点（名字.jar）,然后点击next，直到finish
?2、就可以利用我们自己写的jar包了，导入我们需要写的文件里
二、web.xml做配置
<?xml version="1.0" encoding="UTF-8"?>
<config>
?? ?<!--?
?? ??? ?在这里每加一个配置，就相当于actions.put("/goods", new GoodsAction());
?? ??? ?这样就解决了代码灵活性的问题
?? ? -->
?? ?<action path="/book" type="com.lv.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>
三、正式开发
实体类：Book:
所有Dao类的父类：
public class BaseDao<T> {
/**
?* 通用的增删改方法
?* ?? ?思路：
?* ?? ??? ?1、从传进来的t中读取属性值
?* ?? ??? ?2、往预定义对象中设置了值
?* @param sql
?* @param t
?* @throws Exception
?*/
?? ?public void executeUpdate(String sql,T t,String[] attrs) throws Exception {
//?? ??? ?String[] attrs=new String[] {"bid","bname","price"};
?? ??? ?Connection con=DBAccess.getConnection();
?? ??? ?PreparedStatement ps=con.prepareStatement(sql);
?? ??? ?for (int i = 0; i < attrs.length; i++) {
?? ??? ??? ?Field f = t.getClass().getDeclaredField(attrs[i]);
//?? ??? ??? ?打开访问权限
//?? ??? ??? ?t-->book,f-->bid
?? ??? ??? ?f.setAccessible(true);
?? ??? ??? ?ps.setObject(i+1, f.get(t));
?? ??? ?}
?? ??? ?ps.executeUpdate();
?? ?}
?? ?
? ? }
Dao方法：
package com.lv.dao;
import java.util.List;
import com.lv.entity.Book;
import com.lv.util.BaseDao;
import com.lv.util.PageBean;
import com.lv.util.StringUtils;public class BookDao extends BaseDao<Book>{
?? ?/**
?? ? * 增删改查的通用套路
?? ? * 1、建立连接
?? ? * 2、预定义对象PreparedStatement
?? ? * 3、设置占位符
?? ? * 4、ps.executeUpdate()
?? ? * @throws Exception?
?? ? */
// ? ? ? ? ?? 增加
?? ?public void add(Book book) throws Exception {
?? ??? ?String sql="insert into t_mvc_book values(?,?,?)";
?? ??? ?super.executeUpdate(sql, book, new String[] {"bid","bname","price"});
?? ?}
// ? ? ? ? ?? 修改
?? ?public void edit(Book book) throws Exception {
?? ??? ?String sql="update t_mvc_book set bname= ?,price= ? where bid= ?";
?? ??? ?super.executeUpdate(sql, book, new String[] {"bname","price","bid"});
?? ?}
// ? ? ? ? ?? 删除
?? ?public void delete(Book book) throws Exception {
?? ??? ?String sql="delete from t_mvc_book where bid=?";
?? ??? ?super.executeUpdate(sql, book, new String[] {"bid"});
?? ?}
// ? ? ? ? ?? 查看
?? ?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();
?? ??? ?if(StringUtils.isNotBlank(bname)) {
?? ??? ??? ?sql+=" and bname like '%"+bname+"%'";
?? ??? ?}
?? ??? ?if(bid!=0) {
?? ??? ??? ?sql+=" and bid = "+bid;
?? ??? ?}
?? ??? ?return super.executeQuery(sql, Book.class, pageBean);
?? ?} ??
}
子控制器BookAction:
类需要extends ActionSupport implements ModelDriver<Book>
package com.lv.web;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.lv.dao.BookDao;
import com.lv.entity.Book;
import com.lv.framework.ActionSupport;
import com.lv.framework.ModelDriver;
import com.lv.util.PageBean;
public class BookAction extends ActionSupport implements ModelDriver<Book>{
private Book book=new Book();
private BookDao bd=new BookDao();
@Override
public Book getModel() {
// TODO Auto-generated method stub
return book;
}
// 增删改最终都要跳回查询页面
/**
* 分析增删改查一共有多少结果集的配置
* 查询：BookList.jsp 返回值：list
* 增删改确定：book.action?methodName=list 返回值：toList
* 增删改跳转对应界面：bookEdit.jsp 返回值：toEdit
* @param req
* @param resp
* @return
*/
public String add(HttpServletRequest req, HttpServletResponse resp) {
try {
bd.add(book);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toList";
}
public String list(HttpServletRequest req, HttpServletResponse resp) {
try {
PageBean pageBean=new PageBean();
pageBean.setRequest(req);
List<Book> list = bd.list(book, pageBean);
req.setAttribute("books", list);
req.setAttribute("pageBean", pageBean);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "list";
}
public String delete(HttpServletRequest req, HttpServletResponse resp) {
try {
bd.delete(book);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toList";
}
public String edit(HttpServletRequest req, HttpServletResponse resp) {
try {
bd.edit(book);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toList";
}
// 跳转到新增修改页面
public String toEdit(HttpServletRequest req, HttpServletResponse resp) {
try {
// 如果是跳转修改页面，那么需要做bid条件的精准查询
if(book.getBid()!=0) {
List<Book> list=bd.list(book, null);
req.setAttribute("b", list.get(0));
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toEdit";
}
}
主界面：
<%@ page language='java' contentType='text/html; charset=UTF-8'
?? ?pageEncoding='UTF-8'%>
?? ?<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
?? ?<%@ taglib prefix="z" uri="http://jsp.veryedu.cn"%>
<!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="${pageContext.request.contextPath }/book.action?methodName=list" method='post'>
?? ??? ?<div class='form-group mb-2'>
?? ??? ??? ?<input type='text' class='form-control-plaintext' name='bname'
?? ??? ??? ??? ?placeholder='请输入书籍名称'>
?? ??? ??? ??? ?<!-- 不分页 -->
?? ??? ??? ?<!-- ?? ?<input name="rows" value="false" type="hidden"> -->
?? ??? ?</div>
?? ??? ?<button type='submit' class='btn btn-primary mb-2'>查询</button>
?? ??? ?<a ?class='btn btn-primary mb-2' href="${pageContext.request.contextPath }/book.action?methodName=toEdit">>新增</a>
?? ?</form>?? ?<table class='table table-striped bg-success'>
?? ??? ?<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="${pageBean }"></z:page>
?? ?
</body>
</html>
呈现效果：
?
?增加与修改是同一个界面：
<%@ page language='java' contentType='text/html; charset=UTF-8'
?? ?pageEncoding='UTF-8'%>
?? ?<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
?? ?<%@ taglib prefix="z" uri="http://jsp.veryedu.cn"%>
<!DOCTYPE html PUBLIC '-//W3C//DTD HTML 4.01 Transitional//EN' 'http://www.w3.org/TR/html4/loose.dtd'>
<html>
<head>
<meta http-equiv='Content-Type' content='text/html; charset=UTF-8'>
<link
?? ?href='https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css'
?? ?rel='stylesheet'>
<script
?? ?src='https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js'></script>
<title>新增/修改书籍列表</title></head>
<body>
?? ?<form class="form-inline"
?? ??? ?action="${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>
?增加效果界面：
?修改界面呈现数据：
?本期内容结束~