SpringBoot+Mybatis+MySql增删改查自我小结
- 本项目postman各操作截图
- 注意点
- 1.数据库表在创建时未设置ID自增，等到项目完成后才设置id自增，可能在用本项目做添加操作时不成功
- 2.postman一直报502proxy error错误时，可能需要关闭防火墙，然后重启postman
- [email protected](useGeneratedKeys = true, keyProperty = "id") 在本项目中可以返回插入的自增ID值，若未添加此行代码，数据库中插入数据成功，id也自增，但页面不会返回本条数据的ID值
- 4. @Insert("INSERT INTO USERINFO (name,address) VALUES(#{name},#{address})") SQL语句应大写，但此条语句中涉及到字段名时必须小写，否则报无具体字段getter方法的错误，猜测为使用对象包装的原因，有知道的朋友可以下方留言解答，谢谢！
项目结构图
pom.xml文件
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.5.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.0.1</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>javax.persistence-api</artifactId>
<version>2.2</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
application.properties文件
spring.datasource.url=jdbc:mysql://localhost:3306/mvc?characterEncoding=utf8&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
mybatis.typeAliasesPackage=com.example.demo.domain
DemoApplication类
package com.example.demo;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
@MapperScan("com.example.demo.domain")
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
User类
package com.example.demo.domain;
public class User {
private int id;
private String name;
private String address;
// getter & setter
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", address='" + address + '\'' +
'}';
}
}
userMapper类
package com.example.demo.domain;
import org.apache.ibatis.annotations.*;
import java.util.List;
@Mapper
public interface UserMapper {
@Select("select * from userinfo")
List<User> selectAll();
@Select("select * from userinfo where id= #{id}")
User selectUserById(int id);
@Select("select * from userinfo where name= #{name}")
List<User> selectUserByName(String name);
@Options(useGeneratedKeys = true, keyProperty = "id")
@Insert("insert into userinfo (name,address) values (#{name},#{address})")
Integer addUser(User user);
@Update("update userinfo set name=#{name},address=#{address} where id=#{id}")
Integer updateUser(User user);
@Delete("delete from userinfo where id=#{id}")
Integer deleteUser(Integer id);
}
UserService类
package com.example.demo.service;
import com.example.demo.domain.User;
import com.example.demo.domain.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class UserService {
@Autowired
private UserMapper userMapper;
public List<User> listAll() {
return userMapper.selectAll();
}
public User selectUserById(int id) {
return userMapper.selectUserById(id);
}
public List<User> selectUserByName(String name) {
return userMapper.selectUserByName(name);
}
public Integer addUser(User user) {
return userMapper.addUser(user);
}
public Integer updateUser(User user) {
return userMapper.updateUser(user);
}
public Integer deleteUser(Integer id) {
return userMapper.deleteUser(id);
}
}
UserController类
package com.example.demo.controller;
import com.example.demo.domain.User;
import com.example.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@RequestMapping("user")
@RestController
public class UserController {
@Autowired
private UserService userService;
@GetMapping(value = "/list/all")
public List<User> ListAll() {
return userService.listAll();
}
@GetMapping(value = "/selectUserById")
public User selectUserById(String id) {
User user = userService.selectUserById(Integer.parseInt(id));
return user;
}
@GetMapping(value = "/selectUserByName")
public List<User> selectUserByName(String name) {
return userService.selectUserByName(name);
}
@PostMapping(value = "/addUser")
public Map<String, Object> addUser(User user) {
Map<String, Object> map = new HashMap<String, Object>();
if (userService.addUser(user) == 1) {
Integer id = user.getId();
map.put("success", id);
} else {
map.put("error", 0);
}
return map;
}
@PostMapping(value = "/updateUser")
public Map<String, Object> updateUser(User user) {
Map<String, Object> map = new HashMap<String, Object>();
if (userService.updateUser(user) > 0) {
// Integer id = user.getId();
map.put("success", user);
} else {
map.put("error", 0);
}
return map;
}
@DeleteMapping(value = "/deleteUser")
public Map<String, Object> deleteUser(Integer id) {
Map<String, Object> map = new HashMap<String, Object>();
if (userService.deleteUser(id) > 0) {
// Integer id = user.getId();
map.put("success", 1);
} else {
map.put("error", 0);
}
return map;
}
}
本项目postman各操作截图
1.selectAll
2.selectUserById
3.selectUserByName
4.addUser
5.updateUser
6.deleteUser