PHP Classes

File: vendors/echarts/src/data/DataDiffer.js

Recommend this page to a friend!
  Classes of Jorge Castro   Gentelella BladeOne   vendors/echarts/src/data/DataDiffer.js   Download  
File: vendors/echarts/src/data/DataDiffer.js
Role: Auxiliary data
Content type: text/plain
Description: Auxiliary data
Class: Gentelella BladeOne
Render templates using Bootstrap for presentation
Author: By
Last change:
Date: 3 years ago
Size: 3,762 bytes
 

Contents

Class file image Download
define(function(require) { 'use strict'; function defaultKeyGetter(item) { return item; } function DataDiffer(oldArr, newArr, oldKeyGetter, newKeyGetter) { this._old = oldArr; this._new = newArr; this._oldKeyGetter = oldKeyGetter || defaultKeyGetter; this._newKeyGetter = newKeyGetter || defaultKeyGetter; } DataDiffer.prototype = { constructor: DataDiffer, /** * Callback function when add a data */ add: function (func) { this._add = func; return this; }, /** * Callback function when update a data */ update: function (func) { this._update = func; return this; }, /** * Callback function when remove a data */ remove: function (func) { this._remove = func; return this; }, execute: function () { var oldArr = this._old; var newArr = this._new; var oldKeyGetter = this._oldKeyGetter; var newKeyGetter = this._newKeyGetter; var oldDataIndexMap = {}; var newDataIndexMap = {}; var i; initIndexMap(oldArr, oldDataIndexMap, oldKeyGetter); initIndexMap(newArr, newDataIndexMap, newKeyGetter); // Travel by inverted order to make sure order consistency // when duplicate keys exists (consider newDataIndex.pop() below). // For performance consideration, these code below do not look neat. for (i = 0; i < oldArr.length; i++) { var key = oldKeyGetter(oldArr[i]); var idx = newDataIndexMap[key]; // idx can never be empty array here. see 'set null' logic below. if (idx != null) { // Consider there is duplicate key (for example, use dataItem.name as key). // We should make sure every item in newArr and oldArr can be visited. var len = idx.length; if (len) { len === 1 && (newDataIndexMap[key] = null); idx = idx.unshift(); } else { newDataIndexMap[key] = null; } this._update && this._update(idx, i); } else { this._remove && this._remove(i); } } for (var key in newDataIndexMap) { if (newDataIndexMap.hasOwnProperty(key)) { var idx = newDataIndexMap[key]; if (idx == null) { continue; } // idx can never be empty array here. see 'set null' logic above. if (!idx.length) { this._add && this._add(idx); } else { for (var i = 0, len = idx.length; i < len; i++) { this._add && this._add(idx[i]); } } } } } }; function initIndexMap(arr, map, keyGetter) { for (var i = 0; i < arr.length; i++) { var key = keyGetter(arr[i]); var existence = map[key]; if (existence == null) { map[key] = i; } else { if (!existence.length) { map[key] = existence = [existence]; } existence.push(i); } } } return DataDiffer; });