JSP_Homework_07_0427

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1.做一个图书类Book id,name,price ,get,set访问器，构造方法2个，1个无参，1个有参
做一个测试类，在main中创建3个图书对象，放到list集合中。做一个菜单，可以添加，删除，修改，查询

2.上题的类，在一个JSP页面中，创建一个集合，里面放3个图书，集合循环遍历显示在页面上。

3.在MySQL中创建Book表，里面id,name,price,
用命令实现，
添加一个图书，
根据名称删除图书，
把所有名称是“我”开头的图书删除，
删除全部图书，
把20元以上的图书价格都修改为18.8，
查看全部图书，
查看价格高于10块钱的全部图书

——————————————————

_____大概完成了以上sql命令的持久层实现

——通过maven+mybatis+JSP的方式

____虽然目前的controller层只有一个getAll数据遍历的实现

——————————————————

首先是pom文件：

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.cotomi</groupId>
  <artifactId>test0427</artifactId>
  <version>1.0</version>
  <packaging>war</packaging>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.1.0</version>
      <scope>provided</scope>
    </dependency>

    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.0</version>
      <scope>provided</scope>
    </dependency>

    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>8.0.28</version>
      <scope>compile</scope>
    </dependency>

    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.5.6</version>
      <scope>compile</scope>
    </dependency>

    <!-- https://mvnrepository.com/artifact/javax.servlet/jstl -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.apache.taglibs/taglibs-standard-impl -->
    <dependency>
      <groupId>org.apache.taglibs</groupId>
      <artifactId>taglibs-standard-impl</artifactId>
      <version>1.2.5</version>
      <scope>runtime</scope>
    </dependency>

  </dependencies>
  <build>
    <resources>
      <resource>
        <directory>src/main/java</directory>
        <includes>
          <include>**/*.xml</include>
          <include>**/*.properties</include>
        </includes>
      </resource>
      <resource>
        <directory>src/main/resources</directory>
        <includes>
          <include>**/*.xml</include>
          <include>**/*.properties</include>
        </includes>
      </resource>
    </resources>
  </build>
</project>

然后是Mybatis的SQLMapConfig

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <properties resource="jdbc.properties"></properties>
    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
    <typeAliases>
        <package name="com.cotomi.entity"/>
    </typeAliases>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="${jdbc.driverClassName}"/>
                <property name="url" value="${jdbc.url}"/>
                <property name="username" value="${jdbc.username}"/>
                <property name="password" value="${jdbc.password}"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <package name="com.cotomi.mapper"/>
    </mappers>
</configuration>

jdbc的properties文件：

jdbc.driverClassName=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/school?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai
jdbc.username=root
jdbc.password=root

Mapper层映射的BookMapper接口：

package com.cotomi.mapper;

import com.cotomi.entity.Book;

import java.math.BigDecimal;
import java.util.List;

/**
 * @ClassName BookMapper
 * @Date 2022/4/27 17:50
 * @Author 音无彩名
 * @Description 按照要求实现的应该的功能
 * 添加一个图书，
 * 根据名称删除图书，
 * 把所有名称是“我”开头的图书删除，
 * 删除全部图书，
 * 把20元以上的图书价格都修改为18.8，
 * 查看全部图书，
 * 查看价格高于10块钱的全部图书、
 * .....
 * 这里只是建立持久层的通用CURD操作
 */
public interface BookMapper {
    //批量添加图书（在这里顺便实现了添加一个图书的功能）
    int addBatch(List<Book> bookList);
    //批量添加图书（包括自增的主键）
    int addBatchAll(List<Book> bookList);
    //完整书名删除图书
    int deleteByName(Book book);
    //按照开头的模糊匹配删除图书
    int deleteByNameBegin(String beginName);
    //删除全部图书
    int deleteAll();
    //将高于money1价格的图书全部修改为money2价格
    int updateHighMoneyToOtherMoney(BigDecimal money1, BigDecimal money2);
    //查看全部图书
    List<Book> getAll();
    //查看价格高于money的全部图书
    List<Book> getUpMoneyBooks(BigDecimal money);
}

Mapper层映射的BookMapper.xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.cotomi.mapper.BookMapper">
    <sql id="allBookNoId">
        bookname,bookprice
    </sql>
    <sql id="allBook">
        id, bookname, bookprice
    </sql>
<!--    //批量添加图书（在这里顺便实现了添加一个图书的功能）
    int addBatch(List<Book> bookList);
-->
    <insert id="addBatch">
        insert into book(<include refid="allBookNoId"></include>) values
        <foreach collection="list" item="book" separator=",">(#{book.bookname},#{book.bookprice})</foreach>
    </insert>
<!--    int addBatchAll(List<Book> bookList);-->
    <insert id="addBatchAll">
        insert into book(<include refid="allBook"></include>) values
        <foreach collection="list" item="bookAll" separator=",">
            (#{bookAll.id},#{bookAll.bookname},#{bookAll.bookprice})
        </foreach>
    </insert>
<!--        //完整书名删除图书
    int deleteByName(Book book);
    -->
    <delete id="deleteByName" parameterType="book">
        delete from book where bookname = #{bookname}
    </delete>
<!--//按照开头的模糊匹配删除图书
int deleteByNameBegin(String beginName);-->
    <delete id="deleteByNameBegin" parameterType="string">
        delete from book where bookname like concat(#{beginName},'%')
    </delete>
<!--    //删除全部图书    
int deleteAll();-->
    <delete id="deleteAll">
        delete from book
    </delete>
<!--    //将高于money1价格的图书全部修改为money2价格
    int updateHighMoneyToOtherMoney(BigDecimal money1, BigDecimal money2);
-->
    <update id="updateHighMoneyToOtherMoney">
        update book set bookprice = #{arg1} where bookprice > #{arg0}
    </update>
<!--        //查看全部图书
    List<Book> getAll();-->
    <select id="getAll" resultType="book">
        select <include refid="allBookNoId"></include> from book
    </select>
<!--    //查看价格高于money的全部图书
    List<Book> getUpMoneyBooks(BigDecimal money);-->
    <select id="getUpMoneyBooks" resultType="book">
        select <include refid="allBookNoId"></include> from book where bookprice > #{arg0}
    </select>
</mapper>

Book实体类：

package com.cotomi.entity;

import java.math.BigDecimal;
import java.util.Objects;

/**
 * @ClassName Book
 * @Date 2022/4/27 17:45
 * @Author 音无彩名
 * @Description 对应数据库中book表的实体类
 */
public class Book {
    private Integer id;
    private String bookname;
    private BigDecimal bookprice;

    public Book() {
    }

    public Book(String bookname, BigDecimal bookprice) {
        this.bookname = bookname;
        this.bookprice = bookprice;
    }

    public Book(Integer id, String bookname, BigDecimal bookprice) {
        this.id = id;
        this.bookname = bookname;
        this.bookprice = bookprice;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getBookname() {
        return bookname;
    }

    public void setBookname(String bookname) {
        this.bookname = bookname;
    }

    public BigDecimal getBookprice() {
        return bookprice;
    }

    public void setBookprice(BigDecimal bookprice) {
        this.bookprice = bookprice;
    }

    @Override
    public String toString() {
        return "Book{" +
                "id=" + id +
                ", bookname='" + bookname + '\'' +
                ", bookprice=" + bookprice +
                '}';
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Book book = (Book) o;
        return Objects.equals(id, book.id) && Objects.equals(bookname, book.bookname) && Objects.equals(bookprice, book.bookprice);
    }

    @Override
    public int hashCode() {
        return Objects.hash(id, bookname, bookprice);
    }
}

数据库表创建语句：

CREATE TABLE `book` (
  `id` int NOT NULL AUTO_INCREMENT COMMENT '主键',
  `bookname` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT '书名',
  `bookprice` decimal(10,2) NOT NULL COMMENT '价格',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8mb3;

对于持久层代码功能的Junit测试：

----这里只是测试功能的代码 并无业务功能上的意义

package com.cotomi.test;

import com.cotomi.entity.Book;
import com.cotomi.mapper.BookMapper;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.io.InputStream;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.List;

/**
 * @ClassName MyTest
 * @Date 2022/4/27 18:13
 * @Author 音无彩名
 * @Description TODO
 */
public class MyTest {
    SqlSession sqlSession;
    BookMapper bookMapper;

    @Before
    public void openSqlSession() throws IOException {
        InputStream inputStream = Resources.getResourceAsStream("SqlMapConfig.xml");
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        sqlSession = sqlSessionFactory.openSession();
        bookMapper = sqlSession.getMapper(BookMapper.class);
    }

    @After
    public void closeSqlSession(){
        sqlSession.close();
    }

    @Test
    public void testAddBatch(){
        List<Book> bookList = new ArrayList<>();
        bookList.add(new Book("你的图书5",new BigDecimal("23.5")));
        bookList.add(new Book("你的图书6",new BigDecimal("2.5")));
        System.out.println(bookMapper.addBatch(bookList));
        sqlSession.commit();
    }

    @Test
    public void testAddBatchAll(){
        BigDecimal bigDecimal = new BigDecimal("12.11");
        Book book1 = new Book(9,"我的图书11",bigDecimal);
        Book book2 = new Book(11,"我的图书12",bigDecimal);
        List<Book> bookList = new ArrayList<>();
        bookList.add(book1);
        bookList.add(book2);
        int i = bookMapper.addBatchAll(bookList);
        sqlSession.commit();
        System.out.println(i);
    }

    @Test
    public void testDeleteByName(){
        Book book = new Book();
        book.setBookname("我的图书11");
        System.out.println(bookMapper.deleteByName(book));
        sqlSession.commit();
    }

    @Test
    public void testDeleteByNameBegin(){
        String begin = "我";
        System.out.println(bookMapper.deleteByNameBegin(begin));
        sqlSession.commit();
    }

    @Test
    public void testDeleteAll(){
        System.out.println(bookMapper.deleteAll());
        sqlSession.commit();
    }

    @Test
    public void testUpdateHighMoneyToOtherMoney(){
        System.out.println(bookMapper.updateHighMoneyToOtherMoney(new BigDecimal("20"), new BigDecimal("18.8")));
        sqlSession.commit();
    }

    @Test
    public void testGetAll(){
        List<Book> bookList = bookMapper.getAll();
        bookList.forEach(book -> System.out.println(book));
    }

    @Test
    public void testGetUpMoneyBooks(){
        List<Book> bookList = bookMapper.getUpMoneyBooks(new BigDecimal("10"));
        bookList.forEach(book -> System.out.println(book));
    }

}

因为jsp界面中只要求了输出数据库中文件 所以service层代码只实现了getAll这一个接口，同理controller层中同样只实现了这一个功能

package com.cotomi.service;

import com.cotomi.entity.Book;

import java.util.List;

/**
 * @ClassName BookService
 * @Date 2022/4/27 22:03
 * @Author 音无彩名
 * @Description TODO
 */
public interface BookService {
    //获取所有图书
    List<Book> getAll();
}

package com.cotomi.service.impl;

import com.cotomi.entity.Book;
import com.cotomi.mapper.BookMapper;
import com.cotomi.service.BookService;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

/**
 * @ClassName BookService
 * @Date 2022/4/27 22:03
 * @Author 音无彩名
 * @Description TODO
 */
public class BookServiceImpl implements BookService{
    SqlSession sqlSession;
    BookMapper bookMapper;

    @Override
    public List<Book> getAll() {
        List<Book> bookList = null;
        try {
            this.openSqlSession();
            bookList = bookMapper.getAll();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            this.closeSqlSession();
        }
        return bookList;
    }

    private void openSqlSession() throws IOException {
        InputStream inputStream = Resources.getResourceAsStream("SqlMapConfig.xml");
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        sqlSession = sqlSessionFactory.openSession();
        bookMapper = sqlSession.getMapper(BookMapper.class);
    }

    private void closeSqlSession(){
        sqlSession.close();
    }
}

控制层：

package com.cotomi.controller;

import com.cotomi.entity.Book;
import com.cotomi.service.BookService;
import com.cotomi.service.impl.BookServiceImpl;

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 java.io.IOException;
import java.util.List;

/**
 * @ClassName Page
 * @Date 2022/4/27 21:55
 * @Author 音无彩名
 * @Description TODO
 */
@WebServlet("/show")
public class Page extends HttpServlet {
    @Override
    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String servletPath = request.getServletPath();
        switch (servletPath){
            case "/show":
                doShowAll(request,response);
                break;
            default:
                System.out.println("哒咩");
                break;
        }
    }

    private void doShowAll(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        BookService bookService = new BookServiceImpl();
        List<Book> bookList = bookService.getAll();
        request.setAttribute("bookList",bookList);
        request.getRequestDispatcher("/view/show.jsp").forward(request,response);
        return;
    }
}

对应的展示ShowJSP文件：

<%@ page import="java.util.List" %>
<%@ page import="com.cotomi.entity.Book" %><%--
  Created by IntelliJ IDEA.
  User: 音无彩名
  Date: 2022/4/27
  Time: 21:58
  To change this template use File | Settings | File Templates.
--%>
<%@page language="java" contentType="text/html;charset=utf-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@page isELIgnored="false"%>
<%
    List<Book> bookList = (List<Book>)request.getAttribute("bookList");
%>
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>JSP0427homework</title>
</head>
<body>
<table border="1px" cellspacing="0px" cellpadding="20px">

    <tr>
        <th>书籍名</th>
        <th>价格</th>
    </tr>
    <c:forEach items="${requestScope.bookList}" var="book" varStatus="count">
    <tr>
        <td>${book.bookname}</td>
        <td>${book.bookprice}</td>
    </tr>
    </c:forEach>
</table>
</body>
</html>

<%@page language="java" contentType="text/html;charset=utf-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@page isELIgnored="false"%>
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>JSP0427homework</title>
</head>
<body>
<a href="${pageContext.request.contextPath}/show">一切从这里开始</a>
</body>
</html>

界面截图：

——————————————————————————————————————————————————

————————————————————————————————————

...

 安

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