pip-services3-components-node/src/count/CounterTiming.ts

Component definitions for Pip.Services in Node.js

/** @module count */
import { ICounterTimingCallback } from './ICounterTimingCallback';

/**
 * Callback object returned by {@link ICounters.beginTiming} to end timing
 * of execution block and update the associated counter.
 * 
 * ### Example ###
 * 
 *     let timing = counters.beginTiming("mymethod.exec_time");
 *     try {
 *         ...
 *     } finally {
 *         timing.endTiming();
 *     }
 * 
 */
export class CounterTiming {
	private _start: number;
	private _callback: ICounterTimingCallback;
	private _counter: string;

	/**
	 * Creates a new instance of the timing callback object.
	 * 
	 * @param counter 		an associated counter name
	 * @param callback 		a callback that shall be called when endTiming is called.
	 */
	public constructor(counter: string = null, callback: ICounterTimingCallback = null) {
		this._counter = counter;
		this._callback = callback;
		this._start = new Date().getTime();
	}

	/**
	 * Ends timing of an execution block, calculates elapsed time
	 * and updates the associated counter.
	 */
	public endTiming(): void {
		if (this._callback != null) {
			let elapsed: number = new Date().getTime() - this._start;
			this._callback.endTiming(this._counter, elapsed);
		}
	}
}