Idea创建SpringBoot Demo项目来连接MySQL

Posted 2021-09-15 阳光照不到的王国

本机环境：

系统:mac

工具:IDEA

1. 打开Idea，File-->New-->Project
   
2. 
   
3. 
   

4. 点击Finish之后，Idea会帮我们自动下载以下依赖库。

5. 生成好的项目文件结构
   

    

6. 编辑resource/application.properties，增加以下内容
    

   spring.jpa.hibernate.ddl-auto=create
   #db_example为数据库的名称
   spring.datasource.url=jdbc:mysql://localhost:3306/db_example
   #Mysql数据库的用户名
   spring.datasource.username=root
   #MySQL数据库的密码
   spring.datasource.password=root1234
   spring.datasource.driver-class-name=com.mysql.jdbc.Driver

7. 使用Navicat工具创建db_example数据库
   

    

8. 定义一个User类，属性有姓名和邮箱属性，代码如下：
    

   package com.example.springdemowithmysql.entity;
   
   import javax.persistence.Entity;
   import javax.persistence.GeneratedValue;
   import javax.persistence.GenerationType;
   import javax.persistence.Id;
   
   @Entity
   public class User {
       @Id
       @GeneratedValue(strategy= GenerationType.AUTO)
       private Integer id;
   
       private String name;
   
       private String email;
   
       public Integer getId() {
           return id;
       }
   
       public void setId(Integer id) {
           this.id = id;
       }
   
       public String getName() {
           return name;
       }
   
       public void setName(String name) {
           this.name = name;
       }
   
       public String getEmail() {
           return email;
       }
   
       public void setEmail(String email) {
           this.email = email;
       }
   }

9. 创建UserRepository
    

   package com.example.springdemowithmysql.entity;
   
   // This will be AUTO IMPLEMENTED by Spring into a Bean called userRepository
   // CRUD refers Create, Read, Update, Delete
   
   import org.springframework.data.repository.CrudRepository;
   
   public interface UserRepository extends CrudRepository<User, Integer> {
   
   }

10. 创建MainController
     

    package com.example.springdemowithmysql.controller;
    
    import com.example.springdemowithmysql.entity.User;
    import com.example.springdemowithmysql.entity.UserRepository;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.*;
    
    @Controller //标识这个类是一个Controller
    @RequestMapping("/demo") // 请求的URL依/demo开始
    public class MainController {
        @Autowired //Spring会自动通过userRepository来获取bean
        private UserRepository userRepository;
        @PostMapping(path = "/add")
        public @ResponseBody
        String addUser(@RequestParam String name, @RequestParam String email){
            User user = new User();
            user.setName("wangbl");
            user.setEmail("[e-mail]");
            userRepository.save(user);
            return "Saved";
        }
        @GetMapping("/all")
        public @ResponseBody Iterable<User> getAllUsers(){
            return userRepository.findAll();
        }
    }
    
    

11. 启动项目
     

    mvn spring-boot:run

12. 使用curl进行测试,
    测试add接口
     

    curl localhost:8080/demo/add -d name=wangbl -d email=[e-mail]

        

        测试all接口

curl 'localhost:8080/demo/all'

         
使用Spring Boot连接MySql的demo到此已经结束。祝君成功，有问题欢迎交流。