Current Path : C:/xampp/htdocs/moodle/lib/yuilib/3.17.2/recordset-indexer/ |
Current File : C:/xampp/htdocs/moodle/lib/yuilib/3.17.2/recordset-indexer/recordset-indexer.js |
/* YUI 3.17.2 (build 9c3c78e) Copyright 2014 Yahoo! Inc. All rights reserved. Licensed under the BSD License. http://yuilibrary.com/license/ */ YUI.add('recordset-indexer', function (Y, NAME) { /** * Provides the ability to store multiple custom hash tables referencing records in the recordset. * @module recordset * @submodule recordset-indexer */ /** * Plugin that provides the ability to store multiple custom hash tables referencing records in the recordset. * This utility does not support any collision handling. New hash table entries with a used key overwrite older ones. * @class RecordsetIndexer */ function RecordsetIndexer(config) { RecordsetIndexer.superclass.constructor.apply(this, arguments); } Y.mix(RecordsetIndexer, { NS: "indexer", NAME: "recordsetIndexer", ATTRS: { /** * @description Collection of all the hashTables created by the plugin. * The individual tables can be accessed by the key they are hashing against. * * @attribute hashTables * @public * @type object */ hashTables: { value: { } }, keys: { value: { } } } }); Y.extend(RecordsetIndexer, Y.Plugin.Base, { initializer: function(config) { var host = this.get('host'); //setup listeners on recordset events this.onHostEvent('add', Y.bind("_defAddHash", this), host); this.onHostEvent('remove', Y.bind('_defRemoveHash', this), host); this.onHostEvent('update', Y.bind('_defUpdateHash', this), host); }, destructor: function(config) { }, /** * @description Setup the hash table for a given key with all existing records in the recordset * * @method _setHashTable * @param key {string} A key to hash by. * @return obj {object} The created hash table * @private */ _setHashTable: function(key) { var host = this.get('host'), obj = {}, i = 0, len = host.getLength(); for (; i < len; i++) { obj[host._items[i].getValue(key)] = host._items[i]; } return obj; }, //--------------------------------------------- // Syncing Methods //--------------------------------------------- /** * @description Updates all hash tables when a record is added to the recordset * * @method _defAddHash * @private */ _defAddHash: function(e) { var tbl = this.get('hashTables'); //Go through every hashtable that is stored. //in each hashtable, look to see if the key is represented in the object being added. Y.each(tbl, function(v, key) { Y.each(e.added || e.updated, function(o) { //if the object being added has a key which is being stored by hashtable v, add it into the table. if (o.getValue(key)) { v[o.getValue(key)] = o; } }); }); }, /** * @description Updates all hash tables when a record is removed from the recordset * * @method _defRemoveHash * @private */ _defRemoveHash: function(e) { var tbl = this.get('hashTables'), reckey; //Go through every hashtable that is stored. //in each hashtable, look to see if the key is represented in the object being deleted. Y.each(tbl, function(v, key) { Y.each(e.removed || e.overwritten, function(o) { reckey = o.getValue(key); //if the hashtable has a key storing a record, and the key and the record both match the record being deleted, delete that row from the hashtable if (reckey && v[reckey] === o) { delete v[reckey]; } }); }); }, /** * @description Updates all hash tables when the recordset is updated (a combination of add and remove) * * @method _defUpdateHash * @private */ _defUpdateHash: function(e) { //TODO: It will be more performant to create a new method rather than using _defAddHash, _defRemoveHash, due to the number of loops. See commented code. e.added = e.updated; e.removed = e.overwritten; this._defAddHash(e); this._defRemoveHash(e); /* var tbl = this.get('hashTables'), reckey; Y.each(tbl, function(v, key) { Y.each(e.updated, function(o, i) { //delete record from hashtable if it has been overwritten reckey = o.getValue(key); if (reckey) { v[reckey] = o; } //the undefined case is if more records are updated than currently exist in the recordset. if (e.overwritten[i] && (v[e.overwritten[i].getValue(key)] === e.overwritten[i])) { delete v[e.overwritten[i].getValue(key)]; } // if (v[reckey] === o) { // delete v[reckey]; // } // // //add the new updated record if it has a key that corresponds to a hash table // if (o.getValue(key)) { // v[o.getValue(key)] = o; // } }); }); */ }, //--------------------------------------------- // Public Methods //--------------------------------------------- /** * @description Creates a new hash table. * * @method createTable * @param key {string} A key to hash by. * @return tbls[key] {object} The created hash table * @public */ createTable: function(key) { var tbls = this.get('hashTables'); tbls[key] = this._setHashTable(key); this.set('hashTables', tbls); return tbls[key]; }, /** * @description Get a hash table that hashes records by a given key. * * @method getTable * @param key {string} A key to hash by. * @return table {object} The created hash table * @public */ getTable: function(key) { return this.get('hashTables')[key]; } }); Y.namespace("Plugin").RecordsetIndexer = RecordsetIndexer; }, '3.17.2', {"requires": ["recordset-base", "plugin"]});