入门开发
插入用户信息和查询用户信息
pom文件引入相关依赖
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.8.RELEASE</version>
<relativePath />
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- springboot 整合mybatis -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.1.1</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.21</version>
</dependency>
</dependencies>
配置application.yml文件
datasource:
url: jdbc:mysql://localhost:3306/test
username: root
password: 1234
driver-class-name: com.mysql.cj.jdbc.Driver
mybatis:
#mapper配置文件
mapper-locations: classpath:mapper/*.xml
type-aliases-package: com.kkk.entity
编写mapper接口和sqlMapper文件
@Mapper //否则启动类不知道他是mapper接口
public interface UserMapper {
int insertUser(@Param("username") String username, @Param("age")Integer age);
User selectUser(@Param("id")Integer id);
}
<?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.kkk.mapper.UserMapper">
<insert id="insertUser">
insert into `user`(username,age) values (#{username} , #{age})
</insert>
<select id="selectUser" parameterType="Integer" resultType="User">
select username,age,id from `user` where id = #{id}
</select>
</mapper>
编写service接口和service类
public interface MybatisService {
boolean isInsert(String username,Integer age);
User userList(Integer id);
}
@Service("mybatisService")
public class MybatisServiceImpl implements MybatisService {
@Autowired
private UserMapper userMapper;
@Override
public boolean isInsert(String username, Integer age) {
if(username != null && age != null){
return userMapper.insertUser(username,age) == 1;
}
return false;
}
@Override
public User userList(Integer id) {
return userMapper.selectUser(id);
}
}
编写controller层
@Controller
public class MybatisController {
@Autowired
private MybatisService mybatisService;
@RequestMapping("/isInsert")
@ResponseBody
public String isInsert(String username,Integer age){
if(mybatisService.isInsert(username,age)) return "插入成功";
else return "插入失败";
}
@RequestMapping("/userList")
public String userList(Integer id, Map<String,Object> result){
User user = mybatisService.userList(id);
if(user == null) {
return "error1";
}
int age = user.getAge();
String username = user.getUsername();
int userId = user.getId();
result.put("age",age);
result.put("username",username);
result.put("userId",userId);
return "user";
}
}
前端页面
user.ftl
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8" />
<title></title>
</head>
<body>
${username}
${age}
${userId}
</body>
</html>
error1.ftl
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8" />
<title></title>
</head>
<body>
<h1>失败</h1>
</body>
</html>
编写启动类
注意放在：com.kkk包下
@SpringBootApplication
//扫包范围：当前启动类同级包或者子包下面
public class APP {
public static void main(String[] args) {
SpringApplication.run(APP.class);
}
}
