我正在使用JSF 2.0、Tomcat 7.x和EclipseLink作为JPA提供程序。我想更新一个实体实例,其中包含一个一对一的关联,更准确地说是Booking属性中的User属性名为booker。不幸的是,如果我调用我的updateBooking() API方法,EclipseLink会创建一个新的booker而不是只使用已经存在的用户。以下是Eclipse控制台的堆栈跟踪和相关代码片段 - 感谢您提供一些提示!
堆栈跟踪:
堆栈跟踪:
Caused by: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.1.v20111018-r10243): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '1' for key 'EMAIL'
Error Code: 1062
Call: INSERT INTO user (EMAIL, NAME, PASSWORD) VALUES (?, ?, ?)
bind => [3 parameters bound]
Query: WriteObjectQuery(LogString User - id: 1; name: 1; email: 1;)
at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:324)
at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeDirectNoSelect(DatabaseAccessor.java:840)
...
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '1' for key 'EMAIL'
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
DevelopmentController.java
public String testUpdateBooking(){
String str = "/development.xhtml?faces-redirect=true";
try {
Integer bookingId = 22;
Integer bookerId = 1;
BookerApi api = new BookerApi();
Booking booking = api.readBooking(bookingId);
User booker = api.readUser(bookerId);
booking.setBooker(booker);
api.updateBooking(booking);
message = "DevelopmentController.testUpdateBooking() " + booking;
} catch (RuntimeException exc){
message = "EXCEPTION DevelopmentController.testUpdateBooking();";
exc.printStackTrace();
}
return str;
}
BookerApi.java
public void updateBooking(Booking booking){
emf = Persistence.createEntityManagerFactory(PERSISTENCE_UNIT_NAME);
EntityManager em = emf.createEntityManager();
em.getTransaction().begin();
Booking persBooking = em.find(Booking.class, booking.getId());
persBooking.setCourtNo(booking.getCourtNo());
persBooking.setStart(booking.getStart());
persBooking.setEnd(booking.getEnd());
persBooking.setBooker(booking.getBooker());
em.getTransaction().commit(); // haendelt update implizit, kracht
em.clear();
emf.close();
}
实体预订者属性:
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
Integer id;
@Temporal(TemporalType.DATE)
@Column(nullable = false)
Date start;
@Temporal(TemporalType.DATE)
@Column(nullable = false)
Date end;
@Column(nullable = false)
Integer courtNo;
@OneToOne(fetch = FetchType.EAGER) // Mueller S. 105, 109
@JoinColumn(name = "user")
User booker;
实体用户属性:
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;
@Column(unique = true, nullable = false)
private String name;
@Column(nullable = false)
private String password; // TODO verschluesseln
@Column(unique = true, nullable = false)
private String email;