目录
1. MyBatis-Plus概述
MyBatis-Plus（简称 MP）是一个MyBatis的增强工具，在MyBatis的基础上只做增强不做改变，为简化开发、提高效率而生。
2. MyBatis-Plus代码生成器概述
AutoGenerator 是 MyBatis-Plus 的代码生成器，通过 AutoGenerator 可以快速生成 Entity、Mapper、Mapper XML、Service、Controller 等各个模块的代码，极大的提升了开发效率。
3. 快速入门
3.1 创建工程
设置 Maven
设置自动导入包 Auto Import
设置启动注解 Annotation Processors
3.2 导入依赖
<!--引入springboot依赖-->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.4.RELEASE</version>
</parent>
<dependencies>
<!--引入spring-boot启动器依赖, 添加启动器后web工程常用的依赖会自动帮你引入-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--test-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!--lombok-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<!--mybatis-plus-->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.0.5</version>
</dependency>
<!--mysql-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.16</version>
</dependency>
<!-- velocity 模板引擎, Mybatis Plus 代码生成器需要 -->
<dependency>
<groupId>org.apache.velocity</groupId>
<artifactId>velocity-engine-core</artifactId>
<version>2.0</version>
</dependency>
<!--集成druid连接池-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
<!--Swagger2-->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>2.7.0</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>2.7.0</version>
</dependency>
</dependencies>
<!--打包-->
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>3.3 添加配置文件
resources\application.yml 当中 添加数据库配置信息
# 配置服务端口
server:
port: 8001
# 配置日志输出格式
logging:
pattern:
console: "%clr(%5p) %clr(-){faint} %clr(%-80.80logger{79}){cyan} %clr(:) %m%n"
spring:
# 数据源配置
datasource:
username: root #数据库用户名
password: 163.com #密码
url: jdbc:mysql://localhost:3306/mybatis_db?serverTimezone=GMT%2B8
driver-class-name: com.mysql.cj.jdbc.Driver
type: com.zaxxer.hikari.HikariDataSource #com.alibaba.druid.pool.DruidDataSource
hikari:
connection-test-query: SELECT 1
connection-timeout: 60000
idle-timeout: 500000
max-lifetime: 540000
maximum-pool-size: 12
minimum-idle: 10
pool-name: GuliHikariPool
# sql输出日志配置
mybatis-plus:
configuration:
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl3.4 添加Swagger2配置类
package com.miaxis.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;
@Configuration
@EnableSwagger2
public class SwaggerConfig {
@Bean
public Docket createRestApi() {
return new Docket(DocumentationType.SWAGGER_2)
.apiInfo(apiInfo())
.select()
.apis(RequestHandlerSelectors.basePackage("com.miaxis"))// 指定扫描包下面的注解
.paths(PathSelectors.any())
.build();
}
// 创建api的基本信息
private ApiInfo apiInfo() {
return new ApiInfoBuilder()
.title("集成Swagger2构建RESTful APIs")
.description("集成Swagger2构建RESTful APIs")
.termsOfServiceUrl("https://www.miaxis.com")
.contact("Mickey")
.version("1.0.0")
.build();
}
}3.5 添加统一返回数据格式
-
创建状态码接口类
package com.miaxis.utils;
public interface ResultCode {
/*成功状态码*/
Integer SUCCESS = 20000;
/*失败的状态码*/
Integer ERROR = 20001;
}-
创建统一结果类
package com.miaxis.utils;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;
import java.util.HashMap;
import java.util.Map;
@Data
public class ResponseResult{
private ResponseResult(){}
@ApiModelProperty(value = "是否成功")
private Boolean success;
@ApiModelProperty(value = "状态码")
private Integer code;
@ApiModelProperty(value = "返回消息")
private String message;
@ApiModelProperty(value = "返回的数据")
private Map<String,Object> data = new HashMap<>();
/*提供工具方法*/
public static ResponseResult ok(){
ResponseResult responseResult = new ResponseResult();
responseResult.setSuccess(true);
responseResult.setCode(ResultCode.SUCCESS);
responseResult.setMessage("成功");
return responseResult;
}
public static ResponseResult error(){
ResponseResult responseResult = new ResponseResult();
responseResult.setSuccess(false);
responseResult.setCode(ResultCode.ERROR);
responseResult.setMessage("失败");
return responseResult;
}
public ResponseResult success(Boolean success){
this.setSuccess(success);
return this;
}
public ResponseResult message(String message){
this.setMessage(message);
return this;
}
public ResponseResult code(Integer code){
this.setCode(code);
return this;
}
public ResponseResult data(String key,Object value){
this.data.put(key,value);
return this;
}
public ResponseResult data(Map<String,Object> map){
this.setData(map);
return this;
}
}3.6 添加统一异常处理
-
创建全局异常处理类
package com.miaxis.exception;
import com.miaxis.utils.ResponseResult;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
/*全局异常处理器, 只要发生了异常,如果在自己控制当中 没有去捕获 , 就会到此控制器*/
@ControllerAdvice
public class GlobalExceptionHandler {
@ExceptionHandler(Exception.class)
@ResponseBody
public ResponseResult error(Exception e){
e.printStackTrace();
return ResponseResult.error().message(e.getMessage());
}
//自定义异常
@ExceptionHandler(CustomException.class)
@ResponseBody //返回json数据
public ResponseResult error(CustomException e){
e.printStackTrace();
return ResponseResult.error().code(e.getCode()).message(e.getMsg());
}
}-
创建自定义异常处理类
package com.miaxis.exception;
import lombok.AllArgsConstructor;
import lombok.Data;
@Data
@AllArgsConstructor //生成带参数的构造器
public class CustomException extends RuntimeException{
private Integer code;
private String msg;
}-
在需要的地方，主动抛出异常，进入该方法
throw new CustomException(20001,"数据不存在");3.7 添加代码生成类
/src/test/Java下创建类CodeGenerator
注意修改：输出路径，数据库名、账号、密码、表名
import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.generator.AutoGenerator;
import com.baomidou.mybatisplus.generator.config.DataSourceConfig;
import com.baomidou.mybatisplus.generator.config.GlobalConfig;
import com.baomidou.mybatisplus.generator.config.PackageConfig;
import com.baomidou.mybatisplus.generator.config.StrategyConfig;
import com.baomidou.mybatisplus.generator.config.rules.DateType;
import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;
import org.junit.Test;
public class CodeGenerator {
@Test
public void main() {
// 1、创建代码生成器
AutoGenerator mpg = new AutoGenerator();
// 2、全局配置
GlobalConfig gc = new GlobalConfig();
//配置输出路径 (注意修改)
gc.setOutputDir("D:\\MyWork\\SVN_CGS\\JavaWeb\\spring_boot\\spring_boot_mybatis_plus2\\src\\main\\java");
gc.setAuthor("Mickey");
gc.setOpen(false); //生成后是否打开资源管理器
gc.setFileOverride(false); //重新生成时文件是否覆盖
/*
* mp生成service层代码，默认接口名称第一个字母有 I
* */
gc.setControllerName("%sController");
gc.setServiceName("%sService");
gc.setServiceImplName("%sServiceImpl");
gc.setMapperName("%sMapper");
gc.setXmlName("%sMapper");
gc.setIdType(IdType.ID_WORKER_STR); //主键策略
gc.setDateType(DateType.ONLY_DATE);//定义生成的实体类中日期类型
gc.setSwagger2(true); //开启Swagger2模式
mpg.setGlobalConfig(gc);
// 3、数据源配置
DataSourceConfig dsc = new DataSourceConfig();
dsc.setUrl("jdbc:mysql://localhost:3306/mybatis_db?serverTimezone=GMT%2B8");
dsc.setDriverName("com.mysql.cj.jdbc.Driver");
dsc.setUsername("root");
dsc.setPassword("163.com");
dsc.setDbType(DbType.MYSQL);
mpg.setDataSource(dsc);
// 4、包配置
PackageConfig pc = new PackageConfig();
pc.setModuleName("mybatis"); //模块名
pc.setParent("com.miaxis"); //com.miaxis.模块名称.功能 -> com.miaxis.mybatis.controller
pc.setController("controller");
pc.setEntity("entity");
pc.setService("service");
pc.setMapper("mapper");
mpg.setPackageInfo(pc);
// 5、策略配置
StrategyConfig strategy = new StrategyConfig();
strategy.setInclude("user"); //数据库-表名
//数据库表映射到实体的命名策略 驼峰命名
strategy.setNaming(NamingStrategy.underline_to_camel);
//生成实体时去掉表前缀
//strategy.setTablePrefix("video_");
//数据库表字段映射到实体的命名策略
strategy.setColumnNaming(NamingStrategy.underline_to_camel);
// lombok 模型 @Accessors(chain = true) setter链式操作
strategy.setEntityLombokModel(true);
//restful api风格控制器
strategy.setRestControllerStyle(true);
//url中驼峰转连字符
strategy.setControllerMappingHyphenStyle(true);
mpg.setStrategy(strategy);
// 6、执行
mpg.execute();
}
}3.8 编写启动类
启动类Appliction.java添加包扫描
package com.miaxis;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
@MapperScan("com.miaxis.mybatis.mapper") //启动类Appliction.java添加包扫描
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}3.9 编写测试控制类
@RestController
@RequestMapping("/mybatis/user")
public class UserController {
/*使用代码生成器生成的service当中已经有很多的基础服务 ,直接调用即可*/
@Autowired
private UserService userService;
@GetMapping("/getUserList")
public ResponseResult getUserList(){
//float t = 1/0; //测试异常情况
List<User> list = userService.list(null);
return ResponseResult.ok().data("list",list);
}
}3.10 测试
-
运行启动类
-
直接访问测试 http://localhost:8001/mybatis/user/getUserList
-
通过Swagger测试 http://localhost:8001/swagger-ui.html
4. Demo下载地址
编译器版本：IntelliJ IDEA 2020.3.2 x64
JDK版本：java 1.8.0_111