Delete
public
abstract
@interface
Delete
implements
Annotation
| androidx.room.Delete |
Marks a method in a Dao annotated class as a delete method.
The implementation of the method will delete its parameters from the database.
All of the parameters of the Delete method must either be classes annotated with Entity
or collections/array of it.
Example:
@Dao
public interface MusicDao {
@Delete
public void deleteSongs(Song... songs);
@Delete
public void deleteAlbumAndSongs(Album album, List<Song> songs);
}
If the target entity is specified via entity() then the parameters can be of arbitrary
POJO types that will be interpreted as partial entities. For example:
@Entity
public class Playlist {
@PrimaryKey
long playlistId;
long ownerId;
String name;
@ColumnInfo(defaultValue = "normal")
String category;
}
public class OwnerIdAndCategory {
long ownerId;
String category;
}
@Dao
public interface PlaylistDao {
@Delete(entity = Playlist.class)
public void deleteByOwnerIdAndCategory(OwnerIdAndCategory... idCategory);
}
Summary
Public methods | |
|---|---|
Class<?>
|
entity()
The target entity of the delete method. |
Inherited methods | |
|---|---|
Public methods
entity
public Class<?> entity ()
The target entity of the delete method.
When this is declared, the delete method parameters are interpreted as partial entities when the type of the parameter differs from the target. The POJO class that represents the entity must contain a subset of the fields of the target entity. The fields value will be used to find matching entities to delete.
By default the target entity is interpreted by the method parameters.
| Returns | |
|---|---|
Class<?> |
the target entity of the delete method or none if the method should use the parameter type entities. |