mybatis的配置

mybatis-config.xml的配置

mybatis-config.xml主要功能是用来连接数据库（以Mysql为例）

示例：

<?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.chen.pojo"/>
    </typeAliases>
    <!--
    environments：配置数据库连接环境信息。可以配置多个environment，通过default属性切换不同的environment
    -->
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <!--数据库连接信息-->
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql:///student?useSSL=false"/>
                <property name="username" value="root"/>
                <property name="password" value="1234"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <!--加载sql映射文件-->
        <!-- <mapper resource="com/chen/mapper/UserMapper.xml"/>-->

        <!--Mapper代理方式-->
        <package name="com.chen.mapper"/>
    </mappers>
</configuration>

mybatis依赖：

常用的依赖：

    <!--lomback依赖-->
    <dependency>
         <groupId>org.projectlombok</groupId>
         <artifactId>lombok</artifactId>
         <version>1.18.28</version>
    </dependency>
    <!--mybatis 依赖-->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.5</version>
    </dependency>
    <!--mysql 驱动-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.46</version>
    </dependency>
    <!--junit 单元测试-->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.13</version>
        <scope>test</scope>
    </dependency>

SqlSessionUtil的配置

封装在一个类中，方便使用时进行调用

public class SqlSessionUtil {
        public static SqlSession getSqlSession() {
            SqlSession sqlSession = null;
            try {
                InputStream inputStream = Resources.getResourceAsStream("mybatis-config.xml");
                SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
                sqlSession = sqlSessionFactory.openSession(true);
            } catch (IOException e) {
                e.printStackTrace();
            }
            return sqlSession;
        }
    public static void  closeSqlSession(SqlSession sqlSession) {
            try {
                sqlSession.commit();
                sqlSession.getConnection().close();
                sqlSession.close();
            }catch (Exception e){
                e.printStackTrace();
            }
    }
}

sql映射xml

示例：

<?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.chen.mapper.DeptMapper">

</mapper>