/*
 * Copyright (C) 2010 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 com.android.quicksearchbox.util;

import android.database.sqlite.SQLiteDatabase;

/**
 * Abstract helper base class for SQLite write transactions.
 */
public abstract class SQLiteTransaction {

    /**
     * Executes the statements that form the transaction.
     *
     * @param db A writable database.
     * @return {@code true} if the transaction should be committed.
     */
    protected abstract boolean performTransaction(SQLiteDatabase db);

    /**
     * Runs the transaction against the database. The results are committed if
     * {@link #performTransaction(SQLiteDatabase)} completes normally and returns {@code true}.
     */
    public void run(SQLiteDatabase db) {
        db.beginTransaction();
        try {
            if (performTransaction(db)) {
                db.setTransactionSuccessful();
            }
        } finally {
            db.endTransaction();
        }
    }
}