1：Mysql数据库的连接

1.1 在sts中连接Mysql数据库是在application中写jdbc的连接

spring:
  profiles:
    active:
      - dev
  datasource :
   driver-class-name: com.mysql.jdbc.Driver
   url: jdbc:mysql://localhost:3306/student
   username: root
   password: 123456
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true

1.2对数据库进行增删查改

1.2.1：现在Model层里定义用户

package com.cy.coo.li;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Man {

    @Id
    @GeneratedValue
    private Integer id;
    private Integer age;
    private String cupSize;

    public Man(){

    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public String getCupSize() {
        return cupSize;
    }

    public void setCupSize(String cupSize) {
        this.cupSize = cupSize;
    }

}

1.2.2：运用了一个JpaRepository<>的接口来实现对命名的规范

package com.cy.coo.li;

import java.util.List;

import org.springframework.data.jpa.repository.JpaRepository;

public interface manInterface extends JpaRepository<Man, Integer> {
   //通过年龄查询,因为查出来很可能有很多个，所以使用集合
     public List<Man> findByAge(Integer age);
}

1.2.3：在Dao层实现对数据库的增删查改

package com.cy.coo.li;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.PutMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class ManContent {

    @Autowired
    private manInterface manl;

    @Autowired
    private manService mans;

    /*
     * 查询所有人的数据
     */
    @GetMapping(value = "/man")
    /*
     * List指的是集合.<>是泛型,里面指定了这个集合中存放的是什么数据. List<Man>代表把Man类中的信息的对象都在里面了
     */
    public List<Man> manlist() {
        return manl.findAll();
    }

    /*
     * 添加
     */
    @PostMapping(value = "/man")
    // @RequestParam获取参数
    /*
     * 因为save返回的时添加进去的对象，所以返回类型就是这个对象
     */
    public Man manAdd(@RequestParam("cupSize") String cupSize, @RequestParam("age") Integer age) {
        Man man = new Man();

        man.setCupSize(cupSize);
        man.setAge(age);
        return manl.save(man);
    }

    // 查询
    @GetMapping(value = "/man/{id}")
    //因为
    public Man manFindOne(@PathVariable("id") Integer id) {
        System.out.println(id);
        return manl.findOne(id);

    }
       //更新
    @PutMapping(value="/man{id}")
    public Man manUpdata(@RequestParam(value = "id") Integer id,
    @RequestParam("cupSize") String cupSize, @RequestParam("age") Integer age){
        Man manll=new Man();
        manll.setId(id);
        manll.setAge(age);
        manll.setCupSize(cupSize);
        return manl.save(manll);
    }
    //删除
    @DeleteMapping(value="/man{id}")
    public void manDelete(@RequestParam("id") Integer id){
        //因为delete的返回值为null所以就是没得1返回值
        manl.delete(id);
    }
    //通过年龄查询
     @GetMapping(value="/man/age/{age}")
     public List<Man> manListAge(@PathVariable("age") Integer age){
         return manl.findByAge(age);
     }

     @PostMapping(value="/man/two")
     public void manTwo(){
         mans.InsertTwo();
     }

}

1.2.4service层里实现业务

package com.cy.coo.li;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class manService {

    @Autowired
    private manInterface manl;

    public void InsertTwo(){
        Man manA=new Man();
        manA.setAge(21);
        manA.setCupSize("F");
        manl.save(manA);

        Man manB=new Man();
        manB.setAge(21);
        manB.setCupSize("F");
        manl.save(manB);
    }
}