QueryResultAdapter.kt
/*
* Copyright (C) 2016 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.solver.query.result
import androidx.room.solver.CodeGenScope
/**
* Gets a Cursor and converts it into the return type of a method annotated with @Query.
*/
abstract class QueryResultAdapter(val rowAdapters: List<RowAdapter>) {
val mappings: List<QueryMappedRowAdapter.Mapping>
get() = rowAdapters.filterIsInstance<QueryMappedRowAdapter>().map { it.mapping }
abstract fun convert(outVarName: String, cursorVarName: String, scope: CodeGenScope)
// Indicates whether the cursor should be copied before converting.
// This is important for performance reasons if the Cursor will be traverse more than once.
fun shouldCopyCursor(): Boolean =
rowAdapters.filterIsInstance<PojoRowAdapter>().any { it.relationCollectors.isNotEmpty() }
// Gets a list of additionally accessed table names in sub queries done by the adapter
// (e.g. does done to satisfy @Relation fields).
fun accessedTableNames(): List<String> =
rowAdapters.filterIsInstance<PojoRowAdapter>().flatMap { it.relationTableNames() }
}