SingleColumnRowAdapter.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
import androidx.room.solver.types.CursorValueReader
import androidx.room.vo.ColumnIndexVar

/**
 * Wraps a row adapter when there is only 1 item with 1 column in the response.
 */
class SingleColumnRowAdapter(val reader: CursorValueReader) : RowAdapter(reader.typeMirror()) {
    override fun convert(outVarName: String, cursorVarName: String, scope: CodeGenScope) {
        reader.readFromCursor(outVarName, cursorVarName, "0", scope)
    }

    override fun getDefaultIndexAdapter() = object : IndexAdapter {
        override fun onCursorReady(cursorVarName: String, scope: CodeGenScope) {}

        override fun getIndexVars() = listOf(
            ColumnIndexVar(null, "0")
        )
    }
}