第九章：SSM整合

第九章：SSM整合

9.1：ContextLoaderListener

​ Spring提供了监听器ContextLoaderListener，实现ServletContextListener接口，可监听ServletContext的状态，在web服务器的启动，读取Spring的配置文件，创建Spring的IOC容器，web应用中必须在web.xml中配置。、

<listener><!-- 配置Spring的监听器，在服务启动时加载Spring的配置文件 --><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- 自定义spring配置文件的位置和名称 -->
<context-param><param-name>contextConfigLocation</param-name><param-value>classpath:spring.xml</param-value>
</context-param>

9.2：准备工作

1. 创建模块

   创建一个新的模块，ssm20。

2. 导入依赖

   <packaging>war</packaging><properties><spring.version>5.3.1</spring.version>
   </properties><dependencies><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>${spring.version}</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-beans</artifactId><version>${spring.version}</version></dependency><!--springmvc--><dependency><groupId>org.springframework</groupId><artifactId>spring-web</artifactId><version>${spring.version}</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>${spring.version}</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-jdbc</artifactId><version>${spring.version}</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-aspects</artifactId><version>${spring.version}</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-test</artifactId><version>${spring.version}</version></dependency><!-- Mybatis核心 --><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.7</version></dependency><!--mybatis和spring的整合包--><dependency><groupId>org.mybatis</groupId><artifactId>mybatis-spring</artifactId><version>2.0.6</version></dependency><!-- 连接池 --><dependency><groupId>com.alibaba</groupId><artifactId>druid</artifactId><version>1.0.9</version></dependency><!-- junit测试 --><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version><scope>test</scope></dependency><!-- MySQL驱动 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.16</version></dependency><!-- log4j日志 --><dependency><groupId>log4j</groupId><artifactId>log4j</artifactId><version>1.2.17</version></dependency><!-- https://mvnrepository.com/artifact/com.github.pagehelper/pagehelper --><dependency><groupId>com.github.pagehelper</groupId><artifactId>pagehelper</artifactId><version>5.2.0</version></dependency><!-- 日志 --><dependency><groupId>ch.qos.logback</groupId><artifactId>logback-classic</artifactId><version>1.2.3</version></dependency><!-- ServletAPI --><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.1.0</version><scope>provided</scope></dependency><dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.12.1</version></dependency><dependency><groupId>commons-fileupload</groupId><artifactId>commons-fileupload</artifactId><version>1.3.1</version></dependency><!-- Spring5和Thymeleaf整合包 --><dependency><groupId>org.thymeleaf</groupId><artifactId>thymeleaf-spring5</artifactId><version>3.0.12.RELEASE</version></dependency>
   </dependencies>
   

3. 创建表

   CREATE TABLE t_emp (emp_id int NOT NULL AUTO_INCREMENT,emp_name varchar(20) DEFAULT NULL,age int DEFAULT NULL,gender char(1) DEFAULT NULL,email varchar(50) DEFAULT NULL,PRIMARY KEY (emp_id)
   );
   

9.3：配置Web.xml

<!-- 配置Spring的编码过滤器 -->
<filter><filter-name>CharacterEncodingFilter</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><init-param><param-name>forceEncoding</param-name><param-value>true</param-value></init-param>
</filter>
<filter-mapping><filter-name>CharacterEncodingFilter</filter-name><url-pattern>/*</url-pattern>
</filter-mapping><!-- 配置处理请求方式的过滤器 -->
<filter><filter-name>HiddenHttpMethodFilter</filter-name><filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
</filter>
<filter-mapping><filter-name>HiddenHttpMethodFilter</filter-name><url-pattern>/*</url-pattern>
</filter-mapping><!-- 配置SpringMVC的前端控制器DispatcherServlet -->
<servlet><servlet-name>SpringMVC</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><!-- 设置SpringMVC配置文件自定义的位置和名称 --><init-param><param-name>contextConfigLocation</param-name><param-value>classpath:springmvc.xml</param-value></init-param><!-- 将DispatcherServlet的初始化时间提前到服务器启动时 --><load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping><servlet-name>SpringMVC</servlet-name><url-pattern>/</url-pattern>
</servlet-mapping><!-- 配置Spring的监听器，在服务器启动时加载Spring的配置文件 -->
<listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- 设置Spring配置文件自定义的位置和名称 -->
<context-param><param-name>contextConfigLocation</param-name><param-value>classpath:spring.xml</param-value>
</context-param>

9.4：创建SpringMVC的配置文件并配置

<!-- 扫描控制层组件 -->
<context:component-scan base-package="com.wang.controller"></context:component-scan><!-- 配置视图解析器 -->
<bean id="viewResolver" class="org.thymeleaf.spring5.view.ThymeleafViewResolver"><property name="order" value="1"/><property name="characterEncoding" value="UTF-8"/><property name="templateEngine"><bean class="org.thymeleaf.spring5.SpringTemplateEngine"><property name="templateResolver"><bean class="org.thymeleaf.spring5.templateresolver.SpringResourceTemplateResolver"><!-- 视图前缀 --><property name="prefix" value="/WEB-INF/templates/"/><!-- 视图后缀 --><property name="suffix" value=".html"/><property name="templateMode" value="HTML5"/><property name="characterEncoding" value="UTF-8" /></bean></property></bean></property>
</bean><!-- 配置默认的servlet处理静态资源 -->
<mvc:default-servlet-handler /><!-- 开启mvc的注解驱动 -->
<mvc:annotation-driven /><!-- 配置视图控制器 -->
<mvc:view-controller path="/" view-name="index"></mvc:view-controller>

9.5：搭建MyBatis环境

1. 创建属性文件jdbc.properties

   jdbc.driver=com.mysql.cj.jdbc.Driver
   jdbc.url=jdbc:mysql://localhost:3306/ssm?serverTimezone=UTC
   jdbc.username=root
   jdbc.password=123456
   

2. 创建MyBatis的核心配置文件mybatis-config.xml

   <settings><!-- 将下划线映射为驼峰 --><setting name="mapUnderscoreToCamelCase" value="true"/>
   </settings><plugins><!-- 配置分页插件 --><plugin interceptor="com.github.pagehelper.PageInterceptor"></plugin>
   </plugins>
   

3. 导入日志文件log4j.xml

4. 创建实体类

   package com.wang.pojo;public class Employee {   private Integer empId;private String empName;private Integer age;private String gender;private String email;// 如下省略空参构造、全参构造、get/set方法、toString方法   
   }
   

5. 创建Mapper接口和映射文件

   package com.wang.mapper;public interface EmployeeMapper {// 查询所有的员工信息List<Employee> getAllEmployee();
   }
   

   <select id="getAllEmployee" resultType="Employee">select * from t_emp
   </select>
   

9.6：创建Sping的配置文件并配置

<!-- 扫描组件(除控制层) -->
<context:component-scan base-package="com.wang"><context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan><!-- 引入jdbc.properties -->
<context:property-placeholder location="classpath:jdbc.properties"></context:property-placeholder><!-- 配置数据源 -->
<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"><property name="driverClassName" value="${jdbc.driver}"></property><property name="url" value="${jdbc.url}"></property><property name="username" value="${jdbc.username}"></property><property name="password" value="${jdbc.password}"></property>
</bean><!--配置SqlSessionFactoryBean，可以直接在Spring的IOC中获取SqlSessionFactory-->
<bean class="org.mybatis.spring.SqlSessionFactoryBean"><!--设置MyBatis的核心配置文件的路径--><property name="configLocation" value="classpath:mybatis-config.xml"></property><!--设置数据源--><property name="dataSource" ref="dataSource"></property><!--设置类型别名所对应的包--><property name="typeAliasesPackage" value="com.wang.pojo"></property>
</bean><!-- 配置mapper接口的扫描，可以将指定包下所有的mapper接口通过SqlSession创建代理实现类对象，并将这些对象交给IOC容器管理 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"><property name="basePackage" value="com.wang.mapper"></property>
</bean><!--配置事务管理器-->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"><property name="dataSource" ref="dataSource"></property>
</bean><!-- 开启事务的注解驱动 将使用注解@Transactional标识的方法或类中所有的方法进行事务管理 -->
<tx:annotation-driven transaction-manager="transactionManager" />

9.7：测试功能

1. 创建接口EmployeeService

   package com.wang.service;public interface EmployeeService {// 获取员工的分页信息PageInfo<Employee> getEmployeePage(Integer pageNum);
   }
   

2. 创建实现类EmployeeServiceImpl

   package com.wang.service.impl;@Service
   @Transactional
   public class EmployeeServiceImpl implements EmployeeService {@Autowiredprivate EmployeeMapper employeeMapper;@Overridepublic PageInfo<Employee> getEmployeePage(Integer pageNum) {// 开启分页功能PageHelper.startPage(pageNum, 4);// 查询所有的员工信息List<Employee> list = employeeMapper.getAllEmployee();// 获取分页相关数据PageInfo<Employee> page = new PageInfo<>(list, 5);return page;}
   }
   

3. 创建控制层组件EmployeeController

   package com.wang.controller;@Controller
   public class EmployeeController {@Autowiredprivate EmployeeService employeeService;@GetMapping("/employee/page/{pageNum}")public String getEmployeePage(@PathVariable("pageNum") Integer pageNum, Model model){//获取员工的分页信息PageInfo<Employee> page = employeeService.getEmployeePage(pageNum);//将分页数据共享到请求域中model.addAttribute("page", page);return "employee_list";}
   }
   

4. 创建页面：index.html和employee_list.html

   <!DOCTYPE html>
   <html lang="en" xmlns:th="http://www.thymeleaf.org">
   <head><meta charset="UTF-8"><title>首页</title>
   </head>
   <body>
   <h1>index.html</h1>
   <a th:href="@{/employee/page/1}">查询员工的分页信息</a>
   </body>
   </html>
   

   <!DOCTYPE html>
   <html lang="en" xmlns:th="http://www.thymeleaf.org">
   <head><meta charset="UTF-8"><title>员工列表</title><link rel="stylesheet" th:href="@{/static/css/index_work.css}">
   </head>
   <body>
   <table><tr><th colspan="6">员工列表</th></tr><tr><th>流水号</th><th>员工姓名</th><th>年龄</th><th>性别</th><th>邮箱</th><th>操作</th></tr><tr th:each="employee,status : ${page.list}"><td th:text="${status.count}"></td><td th:text="${employee.empName}"></td><td th:text="${employee.age}"></td><td th:text="${employee.gender}"></td><td th:text="${employee.email}"></td><td><a href="">删除</a><a href="">修改</a></td></tr>
   </table>
   <div style="text-align: center;"><a th:if="${page.hasPreviousPage}" th:href="@{/employee/page/1}">首页</a><a th:if="${page.hasPreviousPage}" th:href="@{'/employee/page/'+${page.prePage}}">上一页</a><span th:each="num : ${page.navigatepageNums}"><a th:if="${page.pageNum == num}" style="color: red;" th:href="@{'/employee/page/'+${num}}" th:text="'['+${num}+']'"></a><a th:if="${page.pageNum != num}" th:href="@{'/employee/page/'+${num}}" th:text="${num}"></a></span><a th:if="${page.hasNextPage}" th:href="@{'/employee/page/'+${page.nextPage}}">下一页</a><a th:if="${page.hasNextPage}" th:href="@{'/employee/page/'+${page.pages}}">末页</a>
   </div>
   </body>
   </html>
   

5. 启动项目