1.导入依赖：
<dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.26</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.5.6</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>5.3.15</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>5.3.5</version> </dependency> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.9.4</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>2.0.6</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.20</version> </dependency>
2.配置静态资源过滤器
<build> <resources> <resource> <directory>src/main/resources</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>true</filtering> </resource> <resource> <directory>src/main/java</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>true</filtering> </resource> </resources> </build>
3.创建mybatis的配置文件
<?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> //这里需要配置具体类的包 不然会报错 找不到该类 <typeAliases> <package name="com.example.pojo"/> </typeAliases> //这里配置一些连接信息 <environments default="development"> <environment id="development"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="com.mysql.cj.jdbc.Driver"/> <property name="url" value="jdbc:mysql://localhost:3306/medical?useUnicode=true&characterEncoding=utf-8"/> <property name="username" value="root"/> <property name="password" value="root"/> </dataSource> </environment> </environments> //配置对应的mapper.xml <mappers> <mapper class="com.example.mapper.UserMapper"/> </mappers> </configuration>
4.创建实体类
@Data public class User { String name; String password; int age; }
5.创建接口类及其mapper.xml
public interface UserMapper { List<User> getUser(); }
<?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.example.mapper.UserMapper"> <select id="getUser" resultType="User"> select * from user ; </select> </mapper>
6.测试
public static void main(String[] args) { String resource = "mybatis-config.xml"; try { InputStream in = Resources.getResourceAsStream(resource); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in); SqlSession sqlSession = factory.openSession(true); UserMapper mapper = sqlSession.getMapper(UserMapper.class); List<User> user = mapper.getUser(); for (User u : user) { System.out.println(u.toString()); } } catch (IOException e) { e.printStackTrace(); } }
