Springdata JPA(2.0.6版本)中相似但不同的东西的方法，findById和getOne，findOneById

findById、getOne和findOneById的区别

代码示例

@GetMapping("/getOne")
  public ResultBean getOne(Long id) {
    return ResultBean.ok(stu2Service.getOne(id));
  }      

@GetMapping("/findById")
  public ResultBean findById(Long id) {
    return ResultBean.ok(stu2Service.findById(id));
  }      

@GetMapping("/findOneById")
  public ResultBean findOneById(Long id) {
    return ResultBean.ok(stu2Service.findOneById(id));
  }      

1. 返回对象不同

public Optional<T> findById(ID id)； 返回的是Optional对象，通过.get()可获取到对象
public T getOne(ID id)； 不是直接返回的对象，但此方法可以获取对象的相关属性值
Stu2 findOneById(Long id);  根据命名规则中自定义实现，可直接返回到对象      

1. 对空值异常的处理不同,此处模拟的是如果Id在数据库中不存在时的异常

findById
          No value present] with root cause      

getOne
  Unable to find com.aust.first.entity.Stu2 with id 20      

findOneById，没有异常出现      

1. SQL语句不同

findById
          SELECT
  stu2x0_.id_ AS id_1_1_0_,
  stu2x0_.admission_time AS admissio2_1_0_,
  stu2x0_.age_ AS age_3_1_0_,
  stu2x0_.created_by AS created_4_1_0_,
  stu2x0_.hobbies_ AS hobbies_5_1_0_,
  stu2x0_.name_ AS name_6_1_0_,
  stu2x0_.phone_ AS phone_7_1_0_,
  stu2x0_.sid_ AS sid_8_1_0_,
  stu2x0_.summary_ AS summary_9_1_0_
FROM
  ls_stu2 stu2x0_
WHERE
  stu2x0_.id_ =?      

getOne          
SELECT
  stu2x0_.id_ AS id_1_1_0_,
  stu2x0_.admission_time AS admissio2_1_0_,
  stu2x0_.age_ AS age_3_1_0_,
  stu2x0_.created_by AS created_4_1_0_,
  stu2x0_.hobbies_ AS hobbies_5_1_0_,
  stu2x0_.name_ AS name_6_1_0_,
  stu2x0_.phone_ AS phone_7_1_0_,
  stu2x0_.sid_ AS sid_8_1_0_,
  stu2x0_.summary_ AS summary_9_1_0_
FROM
  ls_stu2 stu2x0_
WHERE
  stu2x0_.id_ =?      

findOneById         
SELECT
  stu2x0_.id_ AS id_1_1_,
  stu2x0_.admission_time AS admissio2_1_,
  stu2x0_.age_ AS age_3_1_,
  stu2x0_.created_by AS created_4_1_,
  stu2x0_.hobbies_ AS hobbies_5_1_,
  stu2x0_.name_ AS name_6_1_,
  stu2x0_.phone_ AS phone_7_1_,
  stu2x0_.sid_ AS sid_8_1_,
  stu2x0_.summary_ AS summary_9_1_
FROM
  ls_stu2 stu2x0_
WHERE
  stu2x0_.id_ =?