Mybatis 學習筆記四 MyBatis-Plus插件
maven依賴
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus</artifactId>
<version>3.0.5</version>
</dependency>
<dependency>
<groupId>org.apache.velocity</groupId>
<artifactId>velocity-engine-core</artifactId>
<version>2.0</version>
</dependency>
<dependency>
<groupId>org.freemarker</groupId>
<artifactId>freemarker</artifactId>
<version>2.3.28</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.4</version>
<scope>provided</scope>
</dependency>
配置
mybatis配置
conf.xml
<?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>
</configuration>
注意：保持基本配置即可；
spring配置
applicationContext.xml
<?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:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd">
<!--
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/mybatis
username=root
password=root
-->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://127.0.0.1:3306/mybatis"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</bean>
<!-- MyBatis配置 org.mybatis.spring.SqlSessionFactoryBean-->
<bean id="sqlSessionFactory" class="com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="configLocation" value="classpath:conf.xml"/>
<property name="mapperLocations" value="classpath:mapper/**/*Mapper.xml"/>
<property name="typeAliasesPackage" value="meng.mybatis.test"/>
</bean>
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<!--UserMapper接口所在位置-->
<property name="basePackage" value="meng.mybatis.test"/>
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
</bean>
</beans>
mapper配置
userMapper.xml
<?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">
<!-- 命名空間 -->
<mapper namespace="meng.mybatis.test.UserMapper">
<!-- resultType可以定義簡稱 -->
<select id="findUserByUserid" parameterType="int" resultType="meng.mybatis.test.User">
select * from users where id = #{id}
</select>
<select id="findUsers" resultType="meng.mybatis.test.User">
select * from users
</select>
</mapper>
meng.mybatis.test.UserMapper類
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import java.util.List;
public interface UserMapper extends BaseMapper<User> {
List<User> findUsers();
User findUserByUserid(int id);
}
實體類
User.java
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.ToString;
@TableName("users")
@Data
@NoArgsConstructor
@AllArgsConstructor
@ToString
public class User {
private int id;
private String name;
private int age;
@TableField(value = "stu_id")
private String stuId;
}
測試
ApplicationContext context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
UserMapper userMapper = context.getBean(UserMapper.class);
User user = userMapper.selectById(1);
System.out.println(user]");