/// <reference types="node" />
import { Transform } from 'stream';
import { CounterOptions } from './counterOptions';
/**
 * Counts objects
 */
export default class Counter extends Transform {
    static DEFAULT_OPTIONS: {
        counter: (data: any, count: (...args: any[]) => void) => void;
        logger: (...args: any[]) => void;
        prefixComponents: string[];
        suffixComponents: string[];
        thresholds: number[];
        abortOnError: boolean;
    };
    private _options;
    private _defaultCount;
    private readonly _counters;
    /**
     * @constructor
     * @param options Processed counter options
     */
    constructor(options?: {} | CounterOptions);
    /**
     * https://nodejs.org/api/stream.html#stream_transform_transform_chunk_encoding_callback
     * @override
     */
    _transform(chunk: Buffer | string | any, encoding: string, callback: Function): void;
    /**
     * https://nodejs.org/api/stream.html#stream_transform_flush_callback
     * @override
     */
    _flush(callback: Function): void;
    /**
     * Prints current counter to log
     */
    _print(checkThresholds?: boolean): void;
    /**
     * Counts a counter
     */
    _count(counter?: string): void;
}