ssm第二講--Spring和Mybatis整合

整合Mybatis和Spring

本文學自b站狂神，並加上了自己的理解：：狂神說：spring篇

參考文檔

一、準備

1.1步驟：

1. 導入相關的jar包

• junit
• mybatis
• mysql數據庫
• spring相關的
• aop織入
• mybatis-spring【new】

<dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <!--mysql連接數據庫的包-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!--mybatis包-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <!--spring5包-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
        <!--Spring操作數據庫的話，還需要一個spring-jdbc-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
        <!--切面織入包-->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.8.13</version>
        </dependency>
        <!--mybatis和spring整合包-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>
         <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>

2. 編寫配置文件
3. 測試

1.2、回憶mybatis

1. 編寫實體類
2. 編寫核心配置文件
3. 編寫接口
4. 編寫Mapper.xml
5. 測試

Mybatis詳細配置

二、整合

2.1、新建一個com.lxf.pojo包，並在此包下建一個User類：

package com.lxf.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private int id;
    private String name;
    private String pwd;
}

2.2、新建一個com.lxf.mapper包，並在此包下建一個UserMapper接口和一個UserMapper.xml文件

UserMapper接口類：

package com.lxf.mapper;

import com.lxf.pojo.User;

import java.util.List;

public interface UserMapper {
    //獲取所有的user
    List<User> getAllUsers();
}

UserMapper.xml文件：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.lxf.mapper.UserMapper">
    <select id="getAllUsers" resultType="com.lxf.pojo.User">
        select  * from user
    </select>
</mapper>

2.3、新建一個mybatis-config.xml文件：

<?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核心配置文件-->
<configuration>

    <!--設置-->
    <settings>
        <!--配置日誌-->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
        <!--配置駝峯命名映射-->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
        <!--開啓全局緩存-->
        <setting name="cacheEnabled" value="true"/>
    </settings>

    <!--可以給實體類起別名-->
    <typeAliases>
        <package name="com.lxf.pojo"/>
    </typeAliases>

</configuration>

2.4、新建一個spring-dao.xml文件：

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        https://www.springframework.org/schema/aop/spring-aop.xsd">
    <!--
        DataSource:使用spring的數據源替換Mybatis的配置，c3p0 dbcp druid
        這裏使用Spring提供的JDBC
    -->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=utf-8&amp;allowMultiQueries=true"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>
    <!--配置sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:com/lxf/mapper/*.xml"/>
     </bean>

</beans>

2.5、在com.lxf.mapper包下追加一個代理類UserMapperImpl.java：

package com.lxf.mapper;

import com.lxf.pojo.User;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;

public class UserMapperImpl extends SqlSessionDaoSupport implements UserMapper {
    @Override
    public List<User> getAllUsers() {
        return getSqlSession().getMapper(UserMapper.class).getAllUsers();
    }
}

2.6、新建一個applicationContext.xml文件：

<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
        https://www.springframework.org/schema/beans/spring-beans.xsd">
        <!--引入spring-dao.xml文件-->
        <import resource="classpath:spring-dao.xml"/>

        <bean id="userMapperImpl" class="com.lxf.mapper.UserMapperImpl">
                <property name="sqlSessionFactory"  ref="sqlSessionFactory"/>
        </bean>
</beans>

三、測試

在test.java目錄下新建一個Mytest類進行測試：

import com.lxf.mapper.UserMapperImpl;
import com.lxf.pojo.User;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.util.List;

public class Mytest {
    @Test
    public  void getAllUsers(){
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
        List<User> users = applicationContext.getBean("userMapperImpl", UserMapperImpl.class).getAllUsers();
        for (User user : users) {
            System.out.println("user = " + user);
        }
    }
}