SpringBoot学习日志之DAY_03数据库连接之MYBATIS
1.简单介绍
mybatis是目前开发过程当中使用非常普遍的持久层框架，有许多的mybatis插件例如：分页插件，Mybatis Plugin插件等等大大的提高了生产效率。mysql也是目前非常普遍的数据库。
2.创建项目
首先在pom里面添加对应的依赖
<!--spring web 自带tomcat--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!--spring mybatis依赖 --> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <!--spring mysql数据库依赖--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency>复制代码
然后在application.properties里面配置mybatis相关配置
#数据库连接 配置信息 spring.datasource.driver-class-name=com.mysql.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost:3306/springboot?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true spring.datasource.username=root spring.datasource.password=root #mybatis 配置信息 #xml文件位置 我的xml文件位置就在mapper接口包里面 mybatis.mapper-locations=classpath:com.hjljy.cms.mapper/*.xml #别名所在包 mybatis.type-aliases-package=com.hjljy.cms.Entity #驼峰命名规范启动 mybatis.configuration.map-underscore-to-camel-case=true复制代码
由于我的xml是和mapper放在一起的，因此需要在pom文件build当中额外添加
<resources> <resource> <directory>src/main/resources</directory> <filtering>false</filtering> </resource> <resource> <directory>src/main/java</directory> <includes> <include>**/*.xml</include> </includes> <filtering>false</filtering> </resource> </resources>复制代码
接着编写对应的entity，mapper和xml
public class User implements Serializable {
private static final long serialVersionUID = 7026470724648329551L;
private String id;
private String username;
private String password;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
return "User{" + "id='" + id + ''' + ", username='" + username + ''' + ", password='" + password + ''' + '}';
}
}复制代码@Mapper
public interface UserMapper {
User finById(@Param("id")String id);
}复制代码<?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.hjljy.cms.Mapper.UserMapper">
<!--根据ID查找user-->
<select id="finById" resultType="user" parameterType="string">
SELECT username,password FROM user WHERE ID=#{id}
</select>
</mapper>复制代码在数据库存入对应数据
-- ----------------------------
-- Table structure for user
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
`ID` varchar(255) NOT NULL,
`username` varchar(255) DEFAULT NULL,
`password` varchar(255) DEFAULT NULL,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES ('TEST01', '测试一下', '123456');复制代码最后编写测试类进行测试
@RunWith(SpringRunner.class)
@SpringBootTest
public class CmsApplicationTests {
@Autowired
private UserMapper userMapper;
@Test
public void test1() throws Exception {
User user = userMapper.finById("TEST01");
System.out.println(user);
}
}复制代码测试结果：
作者：海加尔金鹰
链接：https://juejin.cn/post/7031057019574435870