SSM 整合

准备工作

创建 Maven Module

导入依赖

<packaging>war</packaging>

<!-- 自定义属性 -->
<properties>
    <spring.version>5.3.1</spring.version>
</properties>

<dependencies>
    <!-- spring 上下文约束依赖 spring-context-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!-- spring 管理 bean依赖  spring-beans -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-beans</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <!-- springmvc 相关依赖 spring-webmvc 、 spring-web -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <!-- 提供声明式管理器 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!-- 管理切面 aspects -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-aspects</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <!-- spring 整合 junit 的依赖 spring-test -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <!-- mybatis 核心依赖 -->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.7</version>
    </dependency>
    <!-- mybatis 整合 spring的依赖 mybatis-spring -->
    <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 依赖-->
    <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>
    <!-- 分页插件 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>
    <!-- spring 的前端控制器需要使用 ServletAPI -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>4.0.1</version>
    </dependency>

    <!-- 处理 json 数据 -->
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.12.1</version>
    </dependency>

    <!-- 文件上传使用依赖 -->
    <dependency>
        <groupId>commons-fileupload</groupId>
        <artifactId>commons-fileupload</artifactId>
        <version>1.3.1</version>
    </dependency>
    <!-- spring 和 Thymeleaf 整合包 -->
    <dependency>
        <groupId>org.thymeleaf</groupId>
        <artifactId>thymeleaf-spring5</artifactId>
        <version>3.0.14.RELEASE</version>
    </dependency>
</dependencies>

创建表

/*
Navicat MySQL Data Transfer

Source Server         : 本地连接
Source Server Version : 80031
Source Host           : localhost:3306
Source Database       : demo

Target Server Type    : MYSQL
Target Server Version : 80031
File Encoding         : 65001

Date: 2022-10-27 17:16:30
*/

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for t_emp
-- ----------------------------
DROP TABLE IF EXISTS `t_emp`;
CREATE TABLE `t_emp` (
  `emp_id` int NOT NULL AUTO_INCREMENT,
  `emp_name` varchar(20) DEFAULT NULL,
  `age` int DEFAULT NULL,
  `sex` char(1) DEFAULT NULL,
  `email` varchar(50) DEFAULT NULL,
  PRIMARY KEY (`emp_id`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

-- ----------------------------
-- Records of t_emp
-- ----------------------------
INSERT INTO `t_emp` VALUES ('1', 'aaa', null, null, null);
INSERT INTO `t_emp` VALUES ('2', 'fdasf', null, null, null);
INSERT INTO `t_emp` VALUES ('3', 'fds', null, null, null);
INSERT INTO `t_emp` VALUES ('4', 'hdfq', null, null, null);
INSERT INTO `t_emp` VALUES ('5', 'ZSADF', null, null, null);

配置 web.xml

需要在resources目录下，新建spring.xml和springmvc.xml文件

<?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">

    <!-- 配置 spring 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>
        <!-- 配置 SpringMVC 配置文件自定义的位置-->
        <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></load-on-startup>

    </servlet>
    <servlet-mapping>
        <servlet-name>SpringMVC</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <!-- 配置 Spring 的监视器，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>

    <!-- 配置 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>


</web-app>

配置 springMVC

<?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:mvc="http://www.springframework.org/schema/mvc"
       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/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">


    <!--扫描控制层组件-->
    <context:component-scan base-package="com.lyq.ssm.controller"/>

    <!-- 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">
                        <!-- /WEB-INF/templates/index.html -->
                        <property name="prefix" value="/WEB-INF/templates/"/>
                        <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></mvc:default-servlet-handler>

    <!--开启 mvc 注解驱动-->
    <mvc:annotation-driven/>

    <!--配置视图控制器-->
    <mvc:view-controller path="/" view-name="index"></mvc:view-controller>

    <!--配置文件上传解析器-->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"></bean>

    <!--配置拦截器-->

    <!--配置异常处理器-->


</beans>

配置 Spring

在 Spring 中配置了 SqlSession 和mapper就可以在mybatis-config.xml省略对应配置

<?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">

    <!--扫描组件，除控制层-->
    <context:component-scan base-package="com.lyq.ssm">
        <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>


    <!-- 引入 jdbc -->
    <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="password" value="${jdbc.password}"></property>
        <property name="username" value="${jdbc.username}"></property>
    </bean>

    <bean class="org.mybatis.spring.SqlSessionFactoryBean">
        <!--设置mybatis核心配置文件的路径-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!--设置数据源-->
        <property name="dataSource" ref="dataSource"/>
        <!--设置类型别名所对应的包-->
        <property name="typeAliasesPackage" value="com.lyq.ssm.pojo"/>

        <!-- 设置映射文件路径，只有映射文件的包和mapper接口的包不一致时才需要设置-->
        <!--<property name="mapperLocations" value="classpath:mappers/*.xml"/>-->
        <!--<property name="plugins">-->
        <!--    <array>-->
        <!--        <bean class="com.github.pagehelper.PageInterceptor"/>-->
        <!--    </array>-->
        <!--</property>-->
    </bean>

    <!-- 配置 mapper 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 管理-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.lyq.ssm.mapper"/>
    </bean>
</beans>

配置事务

在 spring.xml中添加以下代码：

<!-- 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"></tx:annotation-driven>

log4j.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">

<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
    <appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
        <param name="Encoding" value="UTF-8"/>
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%-5p %d{MM-dd HH:mm:ss,SSS} %m
            (%F:%L) \n" />
        </layout>
    </appender>
    <logger name="java.sql">
        <level value="debug"></level>
    </logger>
    <logger name="org.apache.ibatis">
        <level value="info"></level>
    </logger>
    <root>
        <level value="debug"></level>
        <appender-ref ref="STDOUT"/>
    </root>

</log4j:configuration>

员工列表功能

创建EmployeeService以及定义获取列表的方法

public interface EmployeeService {
    List<Employee> getAllEmployee();
}

EmployeeServiceImpl实现EmployeeService中的获取列表方法

@Service
@Transactional
public class EmployeeServiceImpl implements EmployeeService {

    @Autowired
    private EmployeeMapper employeeMapper;
    public List<Employee> getAllEmployee() {
        return employeeMapper.getAllEmployee();
    }
}

创建mapper接口

public interface EmployeeMapper {
    List<Employee> getAllEmployee();
}

在EmployeeMapper类中写对应sql

<mapper namespace="com.lyq.ssm.mapper.EmployeeMapper">

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

编写controller方法

如果想将返回结果变成json形式，需要添加@ResponseBody注解

@Controller
public class EmployController {

    @Autowired
    private EmployeeService employeeService;

    @GetMapping("/employee")
    @ResponseBody
    public List<Employee> getAllEmployee(){
        List<Employee> list = employeeService.getAllEmployee();
        System.out.println(list);
        return list;
    }

}

员工列表分页功能

配置分页插件

在spring.xml 或者 mybatis-config.xml 中配置皆可

以下是mybatis-config.xml

<plugins>
    <!-- 配置分页插件 -->
    <plugin interceptor="com.github.pagehelper.PageInterceptor"></plugin>
</plugins>

在EmployeeService添加分页方法

public interface EmployeeService {
    List<Employee> getAllEmployee();

    /**
     * 获取员工分页信息
     * @param pageNum
     * @return
     */
    PageInfo<Employee> getEmployeePage(Integer pageNum);
}

在实现类中添加对应方法

public PageInfo<Employee> getEmployeePage(Integer pageNum) {
    // 开启分页功能
    PageHelper.startPage(pageNum, 2);

    // 查询所有员工信息
    List<Employee> list = employeeMapper.getAllEmployee();

    // 获取分页相关数据
    PageInfo<Employee> page = new PageInfo<Employee>(list, 1);

    System.out.println(page);
    return page;
}

在 controller 中编写方法返回Json

@GetMapping("/employee/page/{pageNum}")
@ResponseBody
public List<Employee> getEmployeePage(@PathVariable Integer pageNum){
    // 获取员工分页信息
    PageInfo<Employee> pageInfo = employeeService.getEmployeePage(pageNum);
    System.out.println(pageInfo.getList());
    return pageInfo.getList();

}