import { Cache } from './Cache';
import { KeyType } from './KeyType';
import { Metrics } from './metrics/Metrics';
/**
 * Abstract class for all cache implementations. This exists so that its
 * possible to use instanceof with caches like: `obj instanceof AbstractCache`.
 */
export declare abstract class AbstractCache<K extends KeyType, V> implements Cache<K, V> {
    abstract maxSize: number;
    abstract size: number;
    abstract weightedSize: number;
    abstract set(key: K, value: V): V | null;
    abstract getIfPresent(key: K): V | null;
    abstract peek(key: K): V | null;
    abstract has(key: K): boolean;
    abstract delete(key: K): V | null;
    abstract clear(): void;
    abstract keys(): K[];
    abstract cleanUp(): void;
    abstract metrics: Metrics;
}