I have three classes
Album{
Artist albumArtist;
@Persistent(mappedBy = "parent")
@Element(dependent = "true")
List<Song> songs;
}
Song{
Artist singer;
Album parent;
}
Artist{
String name;
}
If I use the Artist instance I create for Album for Song(singer) - I
get an error
javax.jdo.JDOFatalUserException: Detected attempt to establish Album
(1) as the parent of Album(1)/Song(2)/Artist(3) but the entity
identified by Album(1)/Song(2)/Artist(3) is already a child of Album
(1)/Song(2). A parent cannot be established or changed once an object
has been persisted.
CODE - THIS throws the above error
Artist artist = new Artist("First", "LastN", "First Last");
Album album = new Album("Ahat and album", artist, 1978);
Song song = new Song("Som song", album, artist);
album.addSong(song);
dao.makePersistantAndCommit(album);
CODE: This works
Artist artist = new Artist("First", "LastN", "First Last");
Artist artist2 = new Artist("Second", "LastN", "Second Last");
Album album = new Album("Ahat and album", artist, 1978);
Song song = new Song("Som song", album, artist2);
album.addSong(song);
dao.makePersistantAndCommit(album);
>From my app requirements standpoint - I can have an Artist who is the
albumArtist and who is also the singer. And hence I have a need to use
the Artist instance.
Inputs
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