Source: composer-common/lib/model/relationship.js

/*
 * 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.
 */

'use strict';

const Identifiable = require('./identifiable');

/**
* A Relationship is a typed pointer to an instance. I.e the relationship
* with namespace = 'org.acme', type = 'Vehicle' and id = 'ABC' creates
* a pointer that points at an instance of org.acme.Vehicle with the id
* ABC.
* @extends Identifiable
* @see See [Identifiable]{@link module:composer-common.Identifiable}
* @class
* @memberof module:composer-common
*/
class Relationship extends Identifiable {
    /**
     * Create an asset. Use the Factory to create instances.
     * <p>
     * <strong>Note: Only to be called by framework code. Applications should
     * retrieve instances from {@link Factory}</strong>
     * </p>
     *
     * @param {ModelManager} modelManager - The ModelManager for this instance
     * @param {string} ns - The namespace this instance.
     * @param {string} type - The type this instance.
     * @param {string} id - The identifier of this instance.
     * @private
     */
    constructor(modelManager, ns, type, id) {
        super(modelManager, ns, type, id);
        // we use this metatag to identify the instance as a relationship
        this.$class = 'Relationship';
    }

    /**
     * Returns the string representation of this class
     * @return {String} the string representation of the class
     */
    toString() {
        return 'Relationship {id=' + this.getFullyQualifiedIdentifier() +'}';
    }

    /**
     * Determine if this identifiable is a relationship.
     * @return {boolean} True if this identifiable is a relationship,
     * false if not.
     */
    isRelationship() {
        return true;
    }

}

module.exports = Relationship;