springboot+mybatisplus基础项目搭建
1、创建项目
File->New->Project->Maven->。。。->完成。
目录结构：
2、快速创建相关文件
DeptController.java
package com.strex.controller;
import com.strex.entity.DeptEntity;
import com.strex.service.DeptService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
public class DeptController {
@Autowired
private DeptService deptService;
@GetMapping("/insert")
public void insert() {
deptService.insert();
}
// 单条件查询
// http://localhost:8080/find?id=1
@GetMapping("/findOne")
public DeptEntity findOne(Integer id) {
return deptService.selectById(id);
}
@GetMapping("/getList")
public List<DeptEntity> getList(DeptEntity deptEntity) {
return deptService.findList(deptEntity);
}
// http://localhost:8080/insertDept?deptno=23&dname=%E5%A4%96%E4%BA%A4%E9%83%A8&db_source=DB02
/***
* 表中虽然主键字段是自动增长，但是mybatisplus不会自动增长，这里必须传入deptno
* 如果要自动增长需要在实体类中添加注解 type设置自增
*
* @param deptEntity
* @return
*/
@GetMapping("/insertDept")
public String insertDept(DeptEntity deptEntity) {
return deptService.insertDept(deptEntity);
}
@GetMapping("/updateDept")
public String updateDept(DeptEntity deptEntity) {
return deptService.updateDept(deptEntity);
}
}
DeptEntity.java
package com.strex.entity;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;
//查询需要知道主键，指定表名
@Data
@TableName("dept")
public class DeptEntity {
//TableId表示主键 type设置自增
@TableId(value = "deptno",type = IdType.AUTO)
private Integer deptno;
private String dname;
private String db_source;
}
DeptMapper.java
package com.strex.mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.strex.entity.DeptEntity;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;
//这里只需要继承BaseMapper就可以自动实现增删改查，不需要写sql
//Mapper注解为一个实体类
/**
* 参考该博客：https://blog.csdn.net/qq_42381317/article/details/108283395 愿心无迫
*
* 在对应的功能模块添加对应的注解就不会报错，不然会报错，但是能正常运行
* 配上以下注解自自动装配时@Autowired 才不会报找不到错误
*
* @Repository：代表dao层
* @Component：这个惯用实体层
* @Service ： 这个用于service层
* @Controller ： 这个用于Controller
* 这四个注解的功能都是一样的，都是代表某个类注册到Spring中，装配到Bean中
*/
@Mapper
@Repository
public interface DeptMapper extends BaseMapper<DeptEntity> {
//单表增删改查不需要写sql
// @Insert("INSERT INTO DB01.dept (dname,db_source) VALUES ('[ˈteilə]','n. 裁缝师'), ('[ʌnˈkɔnʃəs]','adj. 不省人事的；失去知觉的')")
// void insertOne();
}
DeptService.java
package com.strex.service;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.strex.entity.DeptEntity;
import com.strex.mapper.DeptMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import java.util.List;
@Component
public class DeptService {
@Autowired
private DeptMapper deptMapper;
public void insert() {
System.out.println("调用service成功");
// userMapper.insertOne();
}
public DeptEntity selectById(Integer id) {
DeptEntity deptEntity = deptMapper.selectById(id);
return deptEntity;
}
// 多条件查询
public List<DeptEntity> findList(DeptEntity deptEntity) {
QueryWrapper<DeptEntity> queryWrapper = new QueryWrapper<>();
String dname = deptEntity.getDname();
if (!StringUtils.isEmpty(dname)) {
// 上面的空判断可以不用，而是通过eq的第一个参数，condition boolen
queryWrapper.eq("dname", dname);
// queryWrapper.ge() 小于
// queryWrapper.orderBy()
// queryWrapper.gt() 大于
// queryWrapper.between() 介于。。。之间
}
// 上面的判断另一种写法
queryWrapper.eq(!StringUtils.isEmpty(deptEntity.getDb_source()), "db_source", deptEntity.getDb_source());
return deptMapper.selectList(queryWrapper);
}
public String insertDept(DeptEntity deptEntity) {
return deptMapper.insert(deptEntity) > 0 ? "success" : "fail";
}
public String updateDept(DeptEntity deptEntity) {
return deptMapper.updateById(deptEntity) > 0 ? "success" : "fail";
}
}
MyApplication.java
package com.strex;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class MyApplication {
public static void main(String[] args) {
//这里就只需要让工程运行起来就行了
SpringApplication.run(MyApplication.class);
}
}
pom.xml
<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>4.0.0modelVersion>
<packaging>jarpackaging>
<groupId>springbootdemogroupId>
<artifactId>SpringbootdemoartifactId>
<version>1.0-SNAPSHOTversion>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>2.6.8version>
parent>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
<version>3.3.2version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>8.0.28version>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
<optional>trueoptional>
dependency>
dependencies>
project>
application.yml
#spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
# spring.datasource.url=jdbc:mysql://107.182.184.210:3306/DB01?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8&useSSL=false
# spring.datasource.username='strex'
spring:
datasource:
password: 51**
username: 'st**'
url: jdbc:mysql://***IP***:3306/DB01?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8&useSSL=false
logging:
level:
###打印mybatis日志，sql语句
com.strex.mapper: debug
3、运行
4、打包
在pom文件中添加打包依赖（这里用打包成jar，由于springboot打包成jar继承了server，不需要额外的tomcat，只需要有java环境就可以运行）。
<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>4.0.0modelVersion>
<packaging>jarpackaging>
<groupId>springbootdemogroupId>
<artifactId>SpringbootdemoartifactId>
<version>1.0-SNAPSHOTversion>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>2.6.8version>
parent>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
<version>3.5.2version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>8.0.30version>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
<optional>trueoptional>
dependency>
dependencies>
<build>
<finalName>time-axisfinalName>
<resources>
<resource>
<directory>src/main/javadirectory>
<includes>
<include>**/*.xmlinclude>
includes>
resource>
<resource>
<directory>src/main/resourcesdirectory>
<includes>
<include>**/*.*include>
includes>
resource>
resources>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
<version>2.1.7.RELEASEversion>
plugin>
plugins>
build>
project>
（1）在Maven Lifecycle中双击package打包。
（2）打包成功后会在target文件夹下生成打包后的jar包。
（3）测试运行，在jar包右键就可以测试运行。
（3）也可以在jar包的文件夹右键执行 java -jar ***.jar运行。
（4）运行结果。
