前言：
本片文章采用的是SpringBoot+MybatisPlus+Swagger2，目的是使用
MybatisPlus完成增删改查操作。
- 1、基本的增删改查
MybatisPlus官网(官网内容很详细哦)：https://mp.baomidou.com/
一、增删改查操作
1.Sql语句
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for user
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
`id` int(20) NOT NULL AUTO_INCREMENT COMMENT '主键ID',
`name` varchar(30) DEFAULT NULL COMMENT '姓名',
`age` int(11) DEFAULT NULL COMMENT '年龄',
`email` varchar(50) DEFAULT NULL COMMENT '邮箱',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
SET FOREIGN_KEY_CHECKS = 1;
2.项目结构
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3.使用自动生成插件-生成代码
大家可以参考这篇文章EasyCode(代码神器)
既然是使用了MybatisPlus的话，我们可以将插件自动生成的代码进行删除。
-
UserDao.xml
UserDao.xml - UserDao.java
删除多余代码并使该接口继承BaseMapper
image.png
顺便将service和controller生成的多余代码删除，要不然会报错！
4.pom.xml
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.1.tmp</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>2.5.0</version>
</dependency>
<dependency>
<groupId>com.github.xiaoymin</groupId>
<artifactId>swagger-bootstrap-ui</artifactId>
<version>1.9.3</version>
</dependency>
5 配置文件
application.yml
spring:
# 数据源
datasource:
# 用户名
username: root
# 密码
password: 123456
# 链接
url: jdbc:mysql://localhost:3306/database?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
# 驱动
driver-class-name: com.mysql.jdbc.Driver
#mybatis-plus 配置
mybatis-plus:
mapper-locations: classpath:/mapper/*Dao.xml
#实体扫描，多个package用逗号或者分号分隔
typeAliasesPackage: com.mp.helo.entity
6 配置类
Swagger2Configuration.java
@Configuration
@EnableSwagger2
public class Swagger2Configuration {
public static final String VERSION = "1.0.0";
//api接口包扫描路径
public static final String SWAGGER_SCAN_BASE_PACKAGE = "com.mp.helo.controller";
@Bean
public Docket createRestApi() {
return new Docket(DocumentationType.SWAGGER_2)
.apiInfo(apiInfo())
.select()
.apis(RequestHandlerSelectors.basePackage(SWAGGER_SCAN_BASE_PACKAGE))
.paths(PathSelectors.any()) // 可以根据url路径设置哪些请求加入文档，忽略哪些请求
.build();
}
private ApiInfo apiInfo() {
return new ApiInfoBuilder()
.title("MP接口测试") //设置文档的标题
.description("MybatisPlus接口测试") // 设置文档的描述
.version(VERSION) // 设置文档的版本信息-> 1.0.0 Version information
.termsOfServiceUrl("www.756316064@qq.com") // 设置文档的License信息->1.3 License information
.build();
}
}
6 entity
User.java
@Data
public class User implements Serializable {
private static final long serialVersionUID = -23543490379469815L;
/**
* 主键ID
*/
@TableId(value = "id",type = IdType.AUTO)
private Long id;
/**
* 姓名
*/
private String name;
/**
* 年龄
*/
private Integer age;
/**
* 邮箱
*/
private String email;
}
7 dao
UserDao.java
@Mapper
public interface UserDao extends BaseMapper<User> {
}
8 service
UserService.java
/**
* (User)表服务接口
*
* @author makejava
* @since 2020-05-16 23:11:09
*/
public interface UserService extends IService<User>{
}
UserServiceImpl.java
/**
* (User)表服务实现类
*
* @author makejava
* @since 2020-05-16 23:11:09
*/
@Service("userService")
public class UserServiceImpl extends ServiceImpl<UserDao,User> implements UserService {
}
9 controller
UserController.java
@Api(description = "用户API接口")
@RestController
@RequestMapping("user")
public class UserController {
/**
* 服务对象
*/
@Resource
private UserService userService;
@ApiOperation(value = "新增")
@PostMapping("insert")
public boolean insert(@RequestBody User user){
return this.userService.save(user);
}
@ApiOperation(value = "修改")
@PostMapping("update")
public boolean update(@RequestBody User user){
return this.userService.updateById(user);
}
@ApiOperation(value = "删除")
@GetMapping("deleteById")
public boolean deleteById(@RequestParam("id") Integer id){
return this.userService.removeById(id);
}
@ApiOperation(value = "批量删除")
@GetMapping("deleteBatchById")
public boolean deleteBatchById(@RequestBody List<Integer> id){
return this.userService.removeByIds(id);
}
@ApiOperation(value = "根据ID查询")
@GetMapping("quertUserById")
public User quertUserById(@RequestParam("id") Integer id){
return this.userService.getById(id);
}
@ApiOperation(value = "分页查询")
@GetMapping("quertUserByPage")
public IPage<User> quertUserByPage(@RequestParam("page") Integer page, @RequestParam("limit") Integer limit){
Page<User> userPage = new Page<>();
IPage<User> userIPage = this.userService.page(userPage);
return userIPage;
}
}
10 启动类
HeloApplication.java
@EnableSwagger2
@SpringBootApplication
@MapperScan("com.mp.helo.dao")
public class HeloApplication {
public static void main(String[] args) {
SpringApplication.run(HeloApplication.class, args);
}
}
访问地址：http://127.0.0.1:8080/doc.html
11 测试
image.png
11.1 添加
image.png
可能出现的问题：
"message": "nested exception is org.apache.ibatis.reflection.ReflectionException: Could not set property 'id' of 'class com.mp.helo.entity.User' with value '1236448483748507649' Cause: java.lang.IllegalArgumentException: java.lang.ClassCastException@3a92a1b",
解决办法：
在主键ID上加上该注解即可：
@TableId(type = IdType.AUTO,value = "id")
11.2删除
image.png
11.3 修改
image.png
11.4 分页查询
image.png
11.5 根据ID查询
image.png
