• 整合SSM


    这里通过集成SSM框架,来做一个增删改查图书的小项目。

    一. 环境要求

    环境:

    • IDEA
    • MySQL 5.7.19
    • Tomcat 9
    • Maven 3.6

    要求:

    • 需要熟练掌握MySQL数据库,Spring,JavaWeb及MyBatis知识,简单的前端知识;

    二. 数据库环境

    创建一个存放书籍数据的数据库表

      CREATE DATABASE `ssmbuild`;
    
      USE `ssmbuild`;
    
      CREATE TABLE `books` (
      `bookID` INT(10) NOT NULL AUTO_INCREMENT COMMENT '书id',
      `bookName` VARCHAR(100) NOT NULL COMMENT '书名',
      `bookCounts` INT(11) NOT NULL COMMENT '数量',
      `detail` VARCHAR(200) NOT NULL COMMENT '描述',
      KEY `bookID` (`bookID`)
      ) ENGINE=INNODB DEFAULT CHARSET=utf8
    
      INSERT  INTO `books`(`bookID`,`bookName`,`bookCounts`,`detail`)VALUES
      (1,'Java',1,'从入门到放弃'),
      (2,'MySQL',10,'从删库到跑路'),
      (3,'Linux',5,'从进门到进牢');
      
      
      DROP TABLE IF EXISTS `books`; 这里是用来删除表使用的
    

    三. 基本环境搭建

    1. 新建一Maven项目!ssmbuild , 添加web的支持
    2. 导入相关的pom依赖!
    <dependencies>
       <!--Junit-->
       <dependency>
           <groupId>junit</groupId>
           <artifactId>junit</artifactId>
           <version>4.12</version>
       </dependency>
       <!--数据库驱动-->
       <dependency>
           <groupId>mysql</groupId>
           <artifactId>mysql-connector-java</artifactId>
           <version>5.1.47</version>
       </dependency>
       <!-- 数据库连接池 -->
       <dependency>
           <groupId>com.mchange</groupId>
           <artifactId>c3p0</artifactId>
           <version>0.9.5.2</version>
       </dependency>
    
       <!--Servlet - JSP -->
       <dependency>
           <groupId>javax.servlet</groupId>
           <artifactId>servlet-api</artifactId>
           <version>2.5</version>
       </dependency>
       <dependency>
           <groupId>javax.servlet.jsp</groupId>
           <artifactId>jsp-api</artifactId>
           <version>2.2</version>
       </dependency>
       <dependency>
           <groupId>javax.servlet</groupId>
           <artifactId>jstl</artifactId>
           <version>1.2</version>
       </dependency>
    
       <!--Mybatis-->
       <dependency>
           <groupId>org.mybatis</groupId>
           <artifactId>mybatis</artifactId>
           <version>3.5.2</version>
       </dependency>
       <dependency>
           <groupId>org.mybatis</groupId>
           <artifactId>mybatis-spring</artifactId>
           <version>2.0.2</version>
       </dependency>
    
       <!--Spring-->
       <dependency>
           <groupId>org.springframework</groupId>
           <artifactId>spring-webmvc</artifactId>
           <version>5.1.9.RELEASE</version>
       </dependency>
       <dependency>
           <groupId>org.springframework</groupId>
           <artifactId>spring-jdbc</artifactId>
           <version>5.1.9.RELEASE</version>
       </dependency>
    </dependencies>
    
    1. Maven资源过滤设置
    <build>
       <resources>
           <resource>
               <directory>src/main/java</directory>
               <includes>
                   <include>**/*.properties</include>
                   <include>**/*.xml</include>
               </includes>
               <filtering>false</filtering>
           </resource>
           <resource>
               <directory>src/main/resources</directory>
               <includes>
                   <include>**/*.properties</include>
                   <include>**/*.xml</include>
               </includes>
               <filtering>false</filtering>
           </resource>
       </resources>
    </build>
    
    1. 建立基本结构和配置框架!
    • com.kuang.pojo
    • com.kuang.dao
    • com.kuang.service
    • com.kuang.controller
    • mybatis-config.xml
    <?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>
    
    </configuration>
    
    • applicationContext.xml
    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans.xsd">
    
    </beans>
    

    四. Mybatis层编写

    1. 数据库配置文件 database.properties
    jdbc.driver=com.mysql.jdbc.Driver
    jdbc.url=jdbc:mysql://localhost:3306/ssmbuild?useSSL=true&useUnicode=true&characterEncoding=utf8
    jdbc.username=root
    jdbc.password=123456
    

    这里实际要注意的点,程序在访问时,会出现连接数据库出错的问题,这里把useSSL=true设置成false就访问成功了,暂不知道原因

    1. IDEA关联数据库
    2. 编写MyBatis的核心配置文件(mybatis-config.xml)
    <?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>
       
       <typeAliases>
           <package name="com.kuang.pojo"/>
       </typeAliases>
       <mappers>
           <mapper resource="com/kuang/dao/BookMapper.xml"/>
       </mappers>
    
    </configuration>
    

    注意这里也可以使用下面这种方式,但是必须在resource下面创建com.xdm.dao的包,不然运行时会找不到Mapper接口

    <mapper class="com.xdm.dao.BookMapper"/>
    
    1. 编写数据库对应的实体类 com.kuang.pojo.Books

    使用lombok插件!

    package com.kuang.pojo;
    
    import lombok.AllArgsConstructor;
    import lombok.Data;
    import lombok.NoArgsConstructor;
    
    @Data
    @AllArgsConstructor
    @NoArgsConstructor
    public class Books {
       
       private int bookID;
       private String bookName;
       private int bookCounts;
       private String detail;
       
    }
    
    1. 编写Dao层的 Mapper接口!
    package com.kuang.dao;
    
    import com.kuang.pojo.Books;
    import java.util.List;
    
    public interface BookMapper {
    
       //增加一个Book
       int addBook(Books book);
    
       //根据id删除一个Book
       int deleteBookById(int id);
    
       //更新Book
       int updateBook(Books books);
    
       //根据id查询,返回一个Book
       Books queryBookById(int id);
    
       //查询全部Book,返回list集合
       List<Books> queryAllBook();
    
    }
    
    1. 编写接口对应的 Mapper.xml 文件。需要导入MyBatis的包;(BookMapper.xml,与Mapper接口的名字一致)
    <?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.kuang.dao.BookMapper">
    
       <!--增加一个Book-->
       <insert id="addBook" parameterType="Books">
          insert into ssmbuild.books(bookName,bookCounts,detail)
          values (#{bookName}, #{bookCounts}, #{detail})
       </insert>
    
       <!--根据id删除一个Book-->
       <delete id="deleteBookById" parameterType="int">
          delete from ssmbuild.books where bookID=#{bookID}
       </delete>
    
       <!--更新Book-->
       <update id="updateBook" parameterType="Books">
          update ssmbuild.books
          set bookName = #{bookName},bookCounts = #{bookCounts},detail = #{detail}
          where bookID = #{bookID}
       </update>
    
       <!--根据id查询,返回一个Book-->
       <select id="queryBookById" resultType="Books">
          select * from ssmbuild.books
          where bookID = #{bookID}
       </select>
    
       <!--查询全部Book-->
       <select id="queryAllBook" resultType="Books">
          SELECT * from ssmbuild.books
       </select>
    
    </mapper>
    
    1. 编写Service层的接口和实现类
    package com.kuang.service;
    
    import com.kuang.pojo.Books;
    
    import java.util.List;
    
    //BookService:底下需要去实现,调用dao层
    public interface BookService {
       //增加一个Book
       int addBook(Books book);
       //根据id删除一个Book
       int deleteBookById(int id);
       //更新Book
       int updateBook(Books books);
       //根据id查询,返回一个Book
       Books queryBookById(int id);
       //查询全部Book,返回list集合
       List<Books> queryAllBook();
    }
    

    实现类:

    package com.kuang.service;
    
    import com.kuang.dao.BookMapper;
    import com.kuang.pojo.Books;
    import java.util.List;
    
    public class BookServiceImpl implements BookService {
    
       //调用dao层的操作,设置一个set接口,方便Spring管理
       private BookMapper bookMapper;
    
       public void setBookMapper(BookMapper bookMapper) {
           this.bookMapper = bookMapper;
      }
       
       public int addBook(Books book) {
           return bookMapper.addBook(book);
      }
       
       public int deleteBookById(int id) {
           return bookMapper.deleteBookById(id);
      }
       
       public int updateBook(Books books) {
           return bookMapper.updateBook(books);
      }
       
       public Books queryBookById(int id) {
           return bookMapper.queryBookById(id);
      }
       
       public List<Books> queryAllBook() {
           return bookMapper.queryAllBook();
      }
    }
    

    OK,到此,底层需求操作编写完毕!

    五. Spring层编写

    1. 配置Spring整合MyBatis,我们这里数据源使用c3p0连接池;
    2. 我们去编写Spring整合Mybatis的相关的配置文件;spring-dao.xml
    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns:context="http://www.springframework.org/schema/context"
          xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans.xsd
           http://www.springframework.org/schema/context
           https://www.springframework.org/schema/context/spring-context.xsd">
    
       <!-- 配置整合mybatis -->
       <!-- 1.关联数据库文件 -->
       <context:property-placeholder location="classpath:database.properties"/>
    
       <!-- 2.数据库连接池 -->
       <!--数据库连接池
           dbcp 半自动化操作 不能自动连接
           c3p0 自动化操作(自动的加载配置文件 并且设置到对象里面)
       -->
       <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
           <!-- 配置连接池属性 -->
           <property name="driverClass" value="${jdbc.driver}"/>
           <property name="jdbcUrl" value="${jdbc.url}"/>
           <property name="user" value="${jdbc.username}"/>
           <property name="password" value="${jdbc.password}"/>
    
           <!-- c3p0连接池的私有属性 -->
           <property name="maxPoolSize" value="30"/>
           <property name="minPoolSize" value="10"/>
           <!-- 关闭连接后不自动commit -->
           <property name="autoCommitOnClose" value="false"/>
           <!-- 获取连接超时时间 -->
           <property name="checkoutTimeout" value="10000"/>
           <!-- 当获取连接失败重试次数 -->
           <property name="acquireRetryAttempts" value="2"/>
       </bean>
    
       <!-- 3.配置SqlSessionFactory对象 -->
       <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
           <!-- 把数据库连接池设置到SqlSessionFactory对象的dataSource属性里 -->
           <property name="dataSource" ref="dataSource"/>
           <!-- 配置MyBatis全局配置文件:mybatis-config.xml -->
           <property name="configLocation" value="classpath:mybatis-config.xml"/>
       </bean>
    
       <!-- 4.配置扫描Dao接口包,动态实现Dao接口注入到spring容器中 -->
       <!--解释 :https://www.cnblogs.com/jpfss/p/7799806.html-->
       <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
           <!-- 注入sqlSessionFactory -->
           <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
           <!-- 给出需要扫描Dao接口包 -->
           <property name="basePackage" value="com.kuang.dao"/>
       </bean>
    
    </beans>
    
    1. Spring整合service层的配置文件;spring-service.xml
    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns:context="http://www.springframework.org/schema/context"
          xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd">
    
       <!-- 扫描service相关的bean -->
       <context:component-scan base-package="com.kuang.service" />
    
       <!--BookServiceImpl注入到IOC容器中-->
       <bean id="BookServiceImpl" class="com.kuang.service.BookServiceImpl">
           <property name="bookMapper" ref="bookMapper"/>
       </bean>
    
       <!-- 配置事务管理器 -->
       <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
           <!-- 注入数据库连接池 -->
           <property name="dataSource" ref="dataSource" />
       </bean>
    
    </beans>
    

    Spring层搞定!再次理解一下,Spring就是一个大杂烩,一个容器!对吧!

    六. SpringMVC层编写

    1. web.xml
    <?xml version="1.0" encoding="UTF-8"?>
    <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
            version="4.0">
    
       <!--DispatcherServlet-->
       <servlet>
           <servlet-name>DispatcherServlet</servlet-name>
           <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
           <init-param>
               <param-name>contextConfigLocation</param-name>
               <!--一定要注意:我们这里加载的是总的配置文件,之前被这里坑了!-->  
               <param-value>classpath:applicationContext.xml</param-value>
           </init-param>
           <load-on-startup>1</load-on-startup>
       </servlet>
       <servlet-mapping>
           <servlet-name>DispatcherServlet</servlet-name>
           <url-pattern>/</url-pattern>
       </servlet-mapping>
    
       <!--encodingFilter-->
       <filter>
           <filter-name>encodingFilter</filter-name>
           <filter-class>
              org.springframework.web.filter.CharacterEncodingFilter
           </filter-class>
           <init-param>
               <param-name>encoding</param-name>
               <param-value>utf-8</param-value>
           </init-param>
       </filter>
       <filter-mapping>
           <filter-name>encodingFilter</filter-name>
           <url-pattern>/*</url-pattern>
       </filter-mapping>
       
       <!--Session过期时间-->
       <session-config>
           <session-timeout>15</session-timeout>
       </session-config>
       
    </web-app>
    
    1. spring-mvc.xml
    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns:context="http://www.springframework.org/schema/context"
          xmlns:mvc="http://www.springframework.org/schema/mvc"
          xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/mvc
       https://www.springframework.org/schema/mvc/spring-mvc.xsd">
    
       <!-- 配置SpringMVC -->
       <!-- 1.开启SpringMVC注解驱动 -->
       <mvc:annotation-driven />
       <!-- 2.静态资源默认servlet配置-->
       <mvc:default-servlet-handler/>
    
       <!-- 3.配置jsp 显示ViewResolver视图解析器 -->
       <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
           <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
           <property name="prefix" value="/WEB-INF/jsp/" />
           <property name="suffix" value=".jsp" />
       </bean>
    
       <!-- 4.扫描web相关的bean -->
       <context:component-scan base-package="com.kuang.controller" />
    
    </beans>
    
    1. Spring配置整合文件,applicationContext.xml
    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans.xsd">
    
       <import resource="spring-dao.xml"/>
       <import resource="spring-service.xml"/>
       <import resource="spring-mvc.xml"/>
       
    </beans>
    

    七. 配置文件,暂时结束!Controller 和 视图层编写

    1. BookController 类编写 , 方法一:查询全部书籍
    @Controller
    @RequestMapping("/book")
    public class BookController {
    
       @Autowired
       @Qualifier("BookServiceImpl")
       private BookService bookService;
    
       @RequestMapping("/allBook")
       public String list(Model model) {
           List<Books> list = bookService.queryAllBook();
           model.addAttribute("list", list);
           return "allBook";
      }
    }
    
    1. 编写首页 index.jsp
    <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
    <!DOCTYPE HTML>
    <html>
    <head>
       <title>首页</title>
       <style type="text/css">
           a {
               text-decoration: none;
               color: black;
               font-size: 18px;
          }
           h3 {
                180px;
               height: 38px;
               margin: 100px auto;
               text-align: center;
               line-height: 38px;
               background: deepskyblue;
               border-radius: 4px;
          }
       </style>
    </head>
    <body>
    
    <h3>
       <a href="${pageContext.request.contextPath}/book/allBook">点击进入列表页</a>
    </h3>
    </body>
    </html>
    
    1. 书籍列表页面 allbook.jsp
    <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
    <%@ page contentType="text/html;charset=UTF-8" language="java" %>
    <html>
    <head>
       <title>书籍列表</title>
       <meta name="viewport" content="width=device-width, initial-scale=1.0">
       <!-- 引入 Bootstrap -->
       <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
    </head>
    <body>
    
    <div class="container">
    
       <div class="row clearfix">
           <div class="col-md-12 column">
               <div class="page-header">
                   <h1>
                       <small>书籍列表 —— 显示所有书籍</small>
                   </h1>
               </div>
           </div>
       </div>
    
       <div class="row">
           <div class="col-md-4 column">
               <a class="btn btn-primary" href="${pageContext.request.contextPath}/book/toAddBook">新增</a>
           </div>
       </div>
    
       <div class="row clearfix">
           <div class="col-md-12 column">
               <table class="table table-hover table-striped">
                   <thead>
                   <tr>
                       <th>书籍编号</th>
                       <th>书籍名字</th>
                       <th>书籍数量</th>
                       <th>书籍详情</th>
                       <th>操作</th>
                   </tr>
                   </thead>
    
                   <tbody>
                   <c:forEach var="book" items="${requestScope.get('list')}">
                       <tr>
                           <td>${book.getBookID()}</td>
                           <td>${book.getBookName()}</td>
                           <td>${book.getBookCounts()}</td>
                           <td>${book.getDetail()}</td>
                           <td>
                               <a href="${pageContext.request.contextPath}/book/toUpdateBook?id=${book.getBookID()}">更改</a> |
                               <a href="${pageContext.request.contextPath}/book/del/${book.getBookID()}">删除</a>
                           </td>
                       </tr>
                   </c:forEach>
                   </tbody>
               </table>
           </div>
       </div>
    </div>
    

    1. BookController 类编写 , 方法二:添加书籍
    @RequestMapping("/toAddBook")
    public String toAddPaper() {
       return "addBook";
    }
    
    @RequestMapping("/addBook")
    public String addPaper(Books books) {
       System.out.println(books);
       bookService.addBook(books);
       return "redirect:/book/allBook";
    }
    
    1. 添加书籍页面:addBook.jsp
    <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
    <%@ page contentType="text/html;charset=UTF-8" language="java" %>
    
    <html>
    <head>
       <title>新增书籍</title>
       <meta name="viewport" content="width=device-width, initial-scale=1.0">
       <!-- 引入 Bootstrap -->
       <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
    </head>
    <body>
    <div class="container">
    
       <div class="row clearfix">
           <div class="col-md-12 column">
               <div class="page-header">
                   <h1>
                       <small>新增书籍</small>
                   </h1>
               </div>
           </div>
       </div>
       <form action="${pageContext.request.contextPath}/book/addBook" method="post">
          书籍名称:<input type="text" name="bookName"><br><br><br>
          书籍数量:<input type="text" name="bookCounts"><br><br><br>
          书籍详情:<input type="text" name="detail"><br><br><br>
           <input type="submit" value="添加">
       </form>
    
    </div>
    

    1. BookController 类编写 , 方法三:修改书籍
    @RequestMapping("/toUpdateBook")
    public String toUpdateBook(Model model, int id) {
       Books books = bookService.queryBookById(id);
       System.out.println(books);
       model.addAttribute("book",books );
       return "updateBook";
    }
    
    @RequestMapping("/updateBook")
    public String updateBook(Model model, Books book) {
       System.out.println(book);
       bookService.updateBook(book);
       Books books = bookService.queryBookById(book.getBookID());
       model.addAttribute("books", books);
       return "redirect:/book/allBook";
    }
    
    1. 修改书籍页面 updateBook.jsp
    <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
    <%@ page contentType="text/html;charset=UTF-8" language="java" %>
    
    <html>
    <head>
       <title>修改信息</title>
       <meta name="viewport" content="width=device-width, initial-scale=1.0">
       <!-- 引入 Bootstrap -->
       <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
    </head>
    <body>
    <div class="container">
    
       <div class="row clearfix">
           <div class="col-md-12 column">
               <div class="page-header">
                   <h1>
                       <small>修改信息</small>
                   </h1>
               </div>
           </div>
       </div>
       <form action="${pageContext.request.contextPath}/book/updateBook" method="post">
          <input type="hidden" name="bookID" value="${book.getBookID()}"/>
          书籍名称:<input type="text" name="bookName" value="${book.getBookName()}">
          书籍数量:<input type="text" name="bookCounts" value="${book.getBookCounts()}">
          书籍详情:<input type="text" name="detail" value="${book.getDetail() }"/>
           <input type="submit" value="提交">
       </form>
    
    </div>
    
    1. BookController 类编写 , 方法四:删除书籍
    @RequestMapping("/del/{bookId}")
    public String deleteBook(@PathVariable("bookId") int id) {
       bookService.deleteBookById(id);
       return "redirect:/book/allBook";
    }
    

    配置Tomcat,进行运行!

    项目结构图
    image

    image

    转自:https://mp.weixin.qq.com/s?__biz=Mzg2NTAzMTExNg==&mid=2247484004&idx=1&sn=cef9d881d0a8d7db7e8ddc6a380a9a76&scene=19#wechat_redirect

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  • 原文地址:https://www.cnblogs.com/maol986162214/p/15813393.html
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