Spring Data JPA的低級錯誤

 1 //課程表
 2 @Entity
 3 public class Class {
 4     @GeneratedValue(strategy = GenerationType.AUTO)
 5     @Id
 6     private Long classID;// 課程編號             varchar(20) not null,
 7     private String className;// 課程名稱          varchar(50),
 8     @Temporal(TemporalType.DATE)//(精確到年月日)
 9     private Date beginTime;//  開始時間         date,
10     @Temporal(TemporalType.DATE)//(精確到年月日)
11     private Date endTime;//結束時間             date,
12     private String classInfo;// 課程簡介          text,
13     private double price;// 價格               numeric,
14     private int times;// 課時數               integer,
15     private int classMan;// 課程人數            int,
16 
17     @ManyToOne(cascade = CascadeType.ALL)
18     private Teacher teacher;//主教練         varchar(20),
19 
20 
21     @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "class_")
22     private List<Lesson> lessons;
23 //...省略getter和setter方法

 1 public interface ClassRepository extends JpaRepository<Class,Long> {
 2 
 3     @Query(value = "SELECT * FROM class WHERE classid=:ID",nativeQuery = true)
 4     Class findClassByID(@Param("ID")Long ID);
 5 
 6     @Modifying
 7     @Transactional
 8     @Query(value = "UPDATE class SET times=:times WHERE classid=:classid",nativeQuery = true)
 9     void updateClassTimes(@Param("times")int times,@Param("classid") Long classid);
10 
11 
12     @Query(value = "  select * FROM class where  DATE_FORMAT(begin_time,'%Y%m%d') >=NOW()",nativeQuery = true)
13     List<Class> findClassByAfter();
14 
15     @Query(value = "  select * FROM class where  DATE_FORMAT(begin_time,'%Y%m%d') <NOW()",nativeQuery = true)
16     List<Class> findClassByBefore();
17 
18     Page<Class> findByBeginTimeBefore(Date date,Pageable pageable);
19 
20 }

若是實體類裏面屬性名開頭用大寫字母，

在JPA中就不能經過查詢的方法名和參數名來自動構造一個JPA OQL查詢，

如18行的方法不能經過編譯，

控制檯會提示找不到該屬性名，

千萬告誡本身編碼必定要規範。