自定义MVC的进阶使用-阿里云开发者社区

前言

通用增删改查、通用分页、XML解析反射建模，包括自定义MVC工作原理与低阶使用等等前面一系列的的文章，其实都是为了这篇博客所作的准备。在本篇博客，会将前面十几篇博客内容串联起来，做出一个简单却不平凡的微项目。

一、环境配置

1.1 将框架打包成jar包

将前面我们所写的通用Servlet——框架打包成Jar包

1.2 将Jar包导入新项目

将Jar包导入新项目，并导入相关依赖

1.3 将分页标签相关文件、及相关助手类导入

tag和util

1.4 配置文件

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" version="3.1">
  <display-name>J2EE_Project</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
   <servlet>
    <servlet-name>mvc</servlet-name>
    <servlet-class>com.xqx.framework.DispatherServlet</servlet-class>
    <init-param>
      <param-name>configurationLocation</param-name>
      <param-value>/mvc.xml</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>mvc</servlet-name>
    <url-pattern>*.action</url-pattern>
  </servlet-mapping>
</web-app>

tld文件：自定义标签

<?xml version="1.0" encoding="UTF-8" ?>
<taglib xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-jsptaglibrary_2_1.xsd"
    version="2.1">
  <description>JSTL 1.1 core library</description>
  <display-name>JSTL core</display-name>
  <tlib-version>1.1</tlib-version>
  <short-name>x</short-name>
  <uri>http://jsp.xqx.cn</uri>
  <tag>
        <name>page</name>
        <tag-class>com.xqx.tag.PageTag</tag-class>
        <body-content>JSP</body-content>
        <attribute>
            <name>pageBean</name>
            <required>true</required>
            <rtexprvalue>true</rtexprvalue>
        </attribute>
    </tag>
</taglib>

二、前后台编写

2.1 实体类

package com.xqx.entity;
/**
 * 
 * @author W许潜行
 *
 */
public class Book {
  private int bid;
  private String bname;
  private float price;
  @Override
  public String toString() {
    return "Book [bid=" + bid + ", bname=" + bname + ", price=" + 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;
  }
  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
  }
}

2.2 dao

package com.xqx.dao;
import java.util.List;
import com.xqx.entity.Book;
import com.xqx.util.BaseDao;
import com.xqx.util.PageBean;
import com.xqx.util.StringUtils;
/**Book dao方法 继承BaseDao
 * @author W许潜行 
 * 2023年7月4日 上午10:00:32
 */
public class BookDao extends BaseDao<Book> {
  /**新增
   * @param book
   * @return
   * @throws Exception
   */
  public int add(Book book) throws Exception {
    String sql = "insert into t_mvc_book values(?,?,?)";
    return super.executeUpdate(sql, book, new String[] { "bid", "bname", "price" });
  }
  /**删除
   * @param book
   * @return
   * @throws Exception
   */
  public int delete(Book book) throws Exception {
    String sql = "delete from t_mvc_book where bid =?";
    return super.executeUpdate(sql, book, new String[] { "bid" });
  }
  /**修改
   * @param book
   * @return
   * @throws Exception
   */
  public int update(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" });
  }
  /**查询
   * @param book
   * @param pageBean
   * @return
   * @throws Exception
   */
  public List<Book> list(Book book, PageBean pageBean) throws Exception {
    String sql = "select * from t_mvc_book where 1=1 ";
    int bid = book.getBid();
    String bname = book.getBname();
    if (StringUtils.isNotBlank(bname)) {
      sql += " where bname like '%" + bname + "%'";
    }
    if (bid != 0) {
      sql += " and where bid=" + bid;
    }
    return super.executeQuery(sql, Book.class, pageBean);
  }
}

2.3 Servlet

package com.xqx.web;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.xqx.dao.BookDao;
import com.xqx.entity.Book;
import com.xqx.framework.Action;
import com.xqx.framework.ModelDriver;
import com.xqx.util.PageBean;
/**子控制类
 * @author W许潜行
 * 2023年7月4日 上午10:04:25
 */
public class BookAction extends Action implements ModelDriver<Book> {
  private Book book = new Book();
  BookDao bd = new BookDao();
  /**
   * 查询数据
   * 
   * @param req
   * @param resp
   * @return
   * @throws Exception
   */
  public String list(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    PageBean pageBean = new PageBean();
    // 初始化
    pageBean.setRequest(req);
    List<Book> list = bd.list(book, pageBean);
    req.setAttribute("list", list);
    req.setAttribute("pageBean", pageBean);
    System.out.println("调用了");
    return "list";
  }
  /**
   * 传入编辑页面的值
   * 
   * @param req
   * @param resp
   * @return
   * @throws Exception
   */
  public String toEdit(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    List<Book> list = bd.list(book, null);
    req.setAttribute("edit", list.get(0));
    return "toEdit";
  }
  /**新增
   * @param req
   * @param resp
   * @return
   * @throws Exception
   */
  public String add(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    bd.add(book);
    return "toList";
  }
  /**删除
   * @param req
   * @param resp
   * @return
   * @throws Exception
   */
  public String delete(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    bd.delete(book);
    return "toList";
  }
  /**修改
   * @param req
   * @param resp
   * @return
   * @throws Exception
   */
  public String update(HttpServletRequest req, HttpServletResponse resp) throws Exception {
    bd.update(book);
    return "toList";
  }
  @Override
  public Book getModel() {
    return book;
  }
}

2.4 配置mvc.xml

conf/mvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<config>
  <action path="/book" type="com.xqx.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>

所需要操作的类和方法在该文件配置

2.5 JSP

booList.jsp

<%@ 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="x" uri="http://jsp.xqx.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=ISO-8859-1">
<title>Insert title here</title>
<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;
}
.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="${pageContext.request.contextPath }/book.action?methodName=list" method="post">
    <div class="form-group mb-2">
      <input type="text" class="form-control-plaintext" name="bname"
        placeholder="请输入书籍名称">
    </div>
    <button type="submit" class="btn btn-primary mb-2">查询</button>
        <a class="btn btn-primary mb-2" href="${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><!-- 遍历数据 -->
      <c:forEach items="${list }" var="b">
      <tr>
        <td>${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>
  <!-- 分页导航栏 -->
  <x:page pageBean="${pageBean }"></x:page>  
</body>
</html>

bookEdit.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
  pageEncoding="UTF-8"%>
<%@ taglib uri="http://jsp.xqx.cn" prefix="x"%> 
<%@ 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 edit ? 'add' : 'edit'}" method="post">
    书籍ID：<input type="text" name="bid" value="${edit.bid }"><br>
    书籍名称：<input type="text" name="bname" value="${edit.bname }"><br>
    书籍价格：<input type="text" name="price" value="${edit.price }"><br>
    <input type="submit">
  </form>
</body>
</html>

2.6 运行结果

查询

新增

修改

好啦，本篇博客就到此为止！希望你看完本篇文章有所收获，祝你变得更强！！!

自定义MVC的进阶使用

前言