1 /*
2  * Copyright (C) 2022 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.quicksearchbox.util
18 
19 import android.database.sqlite.SQLiteDatabase
20 
21 /**
22  * Abstract helper base class for asynchronous SQLite queries.
23  *
24  * @param <A> The type of the result of the query. </A>
25  */
26 abstract class SQLiteAsyncQuery<A> {
27   /**
28    * Performs a query and computes some value from the result
29    *
30    * @param db A readable database.
31    * @return The result of the query.
32    */
performQuerynull33   protected abstract fun performQuery(db: SQLiteDatabase?): A
34 
35   /** Runs the query against the database and passes the result to the consumer. */
36   fun run(db: SQLiteDatabase?, consumer: Consumer<A>) {
37     val result = performQuery(db)
38     consumer.consume(result)
39   }
40 }
41