数据库的 CURD

创建一个接口类

package cn.asdasd.demo;

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

import java.util.List;

public interface GirlRepository extends JpaRepository<Girl,Integer> {
    // 通过年龄查询
    public List<Girl> findByAge(Integer age);
}

创建一个控制器类

package cn.asdasd.demo;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
public class GirlController {

    @Autowired
    private GirlRepository girlRepository;

    /**
     * 查询所有女生列表
     * @return
     */
    @GetMapping(value = "/girls")
    public List<Girl> girlList(){
        return girlRepository.findAll();
    }

    /**
     * 添加女生
     * @param cupSize
     * @param age
     * @return
     */
    @PostMapping(value = "/girls")
    public Girl girlAdd(@RequestParam("cupSize") String cupSize,
                          @RequestParam("age") Integer age) {
        Girl girl = new Girl();
        girl.setCupSize(cupSize);
        girl.setAge(age);
        return  girlRepository.save(girl);
    }

    /**
     * 查询
     * @param id
     * @return
     */
    @GetMapping(value = "/girls/{id}")
    public Girl  girlFindOne(@PathVariable("id") Integer id) {
        return girlRepository.findById( id ).orElse(null);
    }

    /**
     * 更新
     * @param id
     * @param cupSize
     * @param age
     * @return
     */
    @PutMapping(value = "/girls/{id}")
    public Girl  girlUpdate(@PathVariable("id") Integer id,
                            @RequestParam("cupSize") String cupSize,
                            @RequestParam("age") Integer age) {
        Girl girl = new Girl();
        girl.setId(id);
        girl.setCupSize(cupSize);
        girl.setAge(age);

        return girlRepository.save(girl);
    }

    /**
     * 删除数据
     * @param id
     */
    @DeleteMapping(value = "/girls/{id}")
    public void   girlDelete(@PathVariable("id") Integer id) {
         girlRepository.deleteById( id);
    }

}