Mybatis学习(一)——配置MyBatis
1. 坐标
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.6</version>
</dependency>
2. Resource配置sqlMapperConfig.xml
用于配置数据库
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://www.mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!-- 配置数据源环境 --> <environments default="development"> <environment id="development"> <transactionManager type="JDBC"></transactionManager> <dataSource type="POOLED"> <property name="driver" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql://127.0.0.1:3306/mybits_test"/> <property name="username" value="root"/> <property name="password" value="xxxxxxxxx"/> </dataSource> </environment> </environments> <!-- 加载映射文件 --> <mappers> <mapper resource="xyz/javaswing/mapper/userMapper.xml"/> </mappers> </configuration>
配置标签<typeAliases>
<typeAliases> <typeAlias type="xyz.javaswing.domain.User" alias="user"/> </typeAliases> <!-- 给全类名参数定义别名,方便查找 -->
<environments > ........
配置标签<mapper>
<!-- 加载映射文件 --> <mappers> <mapper resource="xyz/javaswing/mapper/userMapper.xml"/> </mappers>
3. Resource创建对应domain被名为Mapper相应文件夹,其中创建sql语句配置文件 UserMapper.xml
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://www.mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="userMapper"> <select id="select" resultType="xyz.javaswing.domain.User"> select * from user </select> </mapper>
UserMapper.xml里
1. mapper定义语句大类
2. 使用<select> <delete> <update> 等标签定义居于
3. 使用id 定于具体语句名
4. resultType执行传入参数
参数是全类名
使用#{}取到参数内属性
只有一个参数时#{}取该参数值