一种基于注解一种基于配置文件
一. 基于注解
1. 导入依赖
<dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.2.0</version> </dependency>2. 写一个接口, 直接写SQL
@Mapper public interface UseryMapper { @Insert("insert into table(name, type) value (#{name, jdbcType=INTEGER}, #{type, jdbcType=VARCHAR})") int insertByMap(Map<String, Object> map); @Insert("insert into table(name, type) value (#{name, jdbcType=INTEGER}, #{type, jdbcType=VARCHAR})") int insertByObject(User user); @Select("select * from table where type = #{type}") @Results({ @Result(column = "type", property = "type"), @Result(column = "id", property = "id"), @Result(column = "name", property = "name") }) User findByCategoryType(Integer tpye); // type为主键 @Select("select * from table where name = #{name}") @Results({ @Result(column = "type", property = "type"), @Result(column = "id", property = "id"), @Result(column = "name", property = "name") }) List<User> findByName(String name); // 查询结果可能有多条 // 更新时候 如果传入多个参数必须加@Param注解指定传入的值 @Update("update table set name = #{name} where type = #{type}") int updateByType(@Param("name") String name, @Param("type") Integer type); // 传入一个对象 @Update("update table set name = #{name} where type = #{type }") int updateByObject(User user); @Delete("delete from table where type = #{type}") int deleteByType(Integer type); }其实查询时候可以不写包含@Results在内的所有注解, 但是需要在每一个入参中使用@Param指定参数
@Mapper注解不需要在每一个Mapper里面都写, 只需要在启动类头加上注解即可
@MapperScan(basePackages = "com.mapper")二. 依赖xml配置文件
1. 跟传统的一样, 需要声明一个接口和一个xml配置文件
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper SYSTEM "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.imooc.dataobject.mapper.ProductCategoryMapper"> <resultMap id="BaseResultMap" type="com.User"> <id column="id" property="id" jdbcType="INTEGER"></id> <id column="type" property="type" jdbcType="INTEGER"></id> <id column="name" property="name" jdbcType="VARCHAR"></id> </resultMap> <select id="selectByCName" resultMap="BaseResultMap" parameterType="java.lang.Integer"> select * from table where name = #{name, jdbcType=INTEGER} </select> </mapper>2. yml增加配置路径 mybatis: config-location: classpath:mapper/*.xml