/**
 * @license
 * Copyright 2019 Google LLC
 *
 * 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.
 */
import { PersistenceValue, PersistenceType } from '../../core/persistence';
export declare abstract class BrowserPersistenceClass {
    protected readonly storageRetriever: () => Storage;
    readonly type: PersistenceType;
    protected constructor(storageRetriever: () => Storage, type: PersistenceType);
    _isAvailable(): Promise<boolean>;
    _set(key: string, value: PersistenceValue): Promise<void>;
    _get<T extends PersistenceValue>(key: string): Promise<T | null>;
    _remove(key: string): Promise<void>;
    protected get storage(): Storage;
}