pip-services3-commons-node/src/refer/Reference.ts

Portable abstractions and patterns for Pip.Services in Node.js

/** @module refer */
import { Descriptor } from './Descriptor';

/**
 * Contains a reference to a component and locator to find it.
 * It is used by [[References]] to store registered component references.
 */
export class Reference {
	private _locator: any;
	private _component: any;

	/**
	 * Create a new instance of the reference object and assigns its values.
	 * 
	 * @param locator 		a locator to find the reference.
	 * @param reference 	a reference to component.
	 */
	public constructor(locator: any, component: any) {
		if (component == null)
			throw new Error("Component cannot be null");
		
		this._locator = locator;
		this._component = component;
	}
	
	/**
	 * Matches locator to this reference locator.
	 * 
	 * Descriptors are matched using equal method.
	 * All other locator types are matched using direct comparison.
	 * 
	 * @param locator 	the locator to match. 
	 * @return true if locators are matching and false it they don't.
	 * 
	 * @see [[Descriptor]]
	 */
	public match(locator: any): boolean {
		// Locate by direct reference matching
		if (this._component == locator)
			return true;
		// Locate by direct locator matching
		else if (this._locator instanceof Descriptor)
            return (<Descriptor>this._locator).equals(locator);
		// Locate by direct locator matching
		else if (this._locator != null)
			return this._locator == locator;
		else
			return false;
	}
	
	/**
	 * Gets the stored component reference.
	 * 
	 * @return the component's references.
	 */
	public getComponent(): any { 
		return this._component; 
	}

	/**
	 * Gets the stored component locator.
	 * 
	 * @return the component's locator.
	 */
	public getLocator(): any {
		return this._locator;
	}
}