Upsert.kt
/*
* Copyright (C) 2022 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.room
import androidx.annotation.RequiresApi
import kotlin.reflect.KClass
/**
* Marks a method in a [Dao] annotated class as an upsert (insert or update) method.
*
* The implementation of the method will insert its parameters into the database
* if it does not already exists (checked by primary key). If it already exists,
* it will update its parameters in the database.
*
* All of the parameters of the upsert method must either be classes annotated with [Entity]
* or collections/array of it.
*
* Example:
*
* ```
* @Dao
* interface MusicDao {
* @Upsert
* fun upsertSongs(varargs songs: Song)
*
* @Upsert
* fun upsertBoth(song1: Song, song2: Song)
*
* @Upsert
* fun upsertAlbumWithSongs(album: Album, songs: List<Song>)
* }
* ```
*
* 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
* data class Playlist (
* @PrimaryKey(autoGenerate = true)
* val playlistId: Long,
* val name: String,
* val description: String?,
*
* @ColumnInfo(defaultValue = "normal")
* val category: String,
*
* @ColumnInfo(defaultValue = "CURRENT_TIMESTAMP")
* val createdTime: String,
*
* @ColumnInfo(defaultValue = "CURRENT_TIMESTAMP")
* val lastModifiedTime: String
* )
*
* data class NameAndDescription (
* val name: String,
* val description: String
* )
*
* @Dao
* interface PlaylistDao {
* @Upsert(entity = Playlist::class)
* fun upsertNewPlaylist(nameDescription: NameAndDescription)
* }
* ```
*
* @see [Insert]
* @see [Update]
*/
@Target(AnnotationTarget.FUNCTION)
@Retention(AnnotationRetention.BINARY)
@RequiresApi(16)
public annotation class Upsert(
/**
* The target entity of the upsert method.
*
* When this is declared, the upsert 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 all of the non-null fields without default values of the target entity.
*
* If the target entity contains a [PrimaryKey] that is auto generated, then the POJO
* class doesn't need an equal primary key field, otherwise primary keys must also be present
* in the POJO. If the primary key already exists, only the columns represented by the partial
* entity fields will be updated
*
* By default the target entity is interpreted by the method parameters.
*
* @return the target entity of the upsert method or none if the method should use the
* parameter type entities.
*/
val entity: KClass<*> = Any::class,
)