1 /**********************************************************  2 * JavaScript实现的ArrayList类   3 *   4 * @author {yangl}  5 * @version $Revision: 0.5 $ $Date: 2008/04/02 15:00:00 $  6 * @description  7 * Method:  8 * add(element);  9 * addElementAt(index, element); 10 * contains(element); 11 * get(index); 12 * isEmpty(index); 13 * indexOf(element); 14 * lastIndexOf(element); 15 * remove() 16 * setElementAt(index, element); 17 * size(); 18 * toString(); 19 * @example 20 * var arrList = new ArrayList(); 21 * //var arrList = new ArrayList(10); 22 * arrList.add("000"); 23 * arrList.add("001"); 24 * arrList.add("002"); 25 * 26 *********************************************************/ 27 // JavaScript ArrayList 28 /**//** 29 Method: 30         add(element); 31         addElementAt(index, element); 32         contains(element); 33         get(index); 34         isEmpty(index); 35         indexOf(element); 36         lastIndexOf(element); 37         remove(index); 38         setElementAt(index, element); 39         size(); 40         toString(); 41 */ 42 /**//** 43 Example: 44         var arrList = new ArrayList(); 45         //var arrList = new ArrayList(10); 46         arrList.add("000"); 47         arrList.add("001"); 48         arrList.add("002"); 49 */ 50 var ArrayList = function() { 51     var args = ArrayList.arguments; 52     var initialCapacity = 10; 53  54     if (args != null && args.length > 0) { 55         initialCapacity = args[0]; 56     } 57  58     var elementData = new Array(initialCapacity); 59     var elementCount = 0; 60  61     this.size = function() { 62         return elementCount; 63     }; 64  65     this.add = function(element) { 66         //alert("add"); 67         ensureCapacity(elementCount + 1); 68         elementData[elementCount++] = element; 69         return true; 70     }; 71  72     this.addElementAt = function(index, element) { 73         //alert("addElementAt"); 74         if (index > elementCount || index < 0) { 75             alert("IndexOutOfBoundsException, Index: " + index + ", Size: " + elementCount); 76             return; 77             //throw (new Error(-1,"IndexOutOfBoundsException, Index: "+index+", Size: " + elementCount)); 78         } 79         ensureCapacity(elementCount + 1); 80         for (var i = elementCount + 1; i > index; i--) { 81             elementData[i] = elementData[i - 1]; 82         } 83         elementData[index] = element; 84         elementCount++; 85     }; 86  87     this.setElementAt = function(index, element) { 88         //alert("setElementAt"); 89         if (index > elementCount || index < 0) { 90             alert("IndexOutOfBoundsException, Index: " + index + ", Size: " + elementCount); 91             return; 92             //throw (new Error(-1,"IndexOutOfBoundsException, Index: "+index+", Size: " + elementCount)); 93         } 94         elementData[index] = element; 95     }; 96  97     this.toString = function() { 98         //alert("toString()"); 99         var str = "{";100         for (var i = 0; i < elementCount; i++) {101             if (i > 0) {102                 str += ",";103             }104             str += elementData[i];105         }106         str += "}";107         return str;108     };109 110     this.get = function(index) {111         //alert("elementAt");112         if (index >= elementCount) {113             alert("ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount);114             return;115             //throw ( new Error( -1,"ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount ) );116         }117         return elementData[index];118     };119 120     this.remove = function(index) {121         if (index >= elementCount) {122             alert("ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount);123             //return;124             throw (new Error(-1, "ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount));125         }126         var oldData = elementData[index];127         for (var i = index; i < elementCount - 1; i++) {128             elementData[i] = elementData[i + 1];129         }130         elementData[elementCount - 1] = null;131         elementCount--;132         return oldData;133     };134 135     this.isEmpty = function() {136         return elementCount == 0;137     };138 139     this.indexOf = function(elem) {140         //alert("indexOf");141         for (var i = 0; i < elementCount; i++) {142             if (elementData[i] == elem) {143                 return i;144             }145         }146         return -1;147     };148 149     this.lastIndexOf = function(elem) {150         for (var i = elementCount - 1; i >= 0; i--) {151             if (elementData[i] == elem) {152                 return i;153             }154         }155         return -1;156     };157 158     this.contains = function(elem) {159         return this.indexOf(elem) >= 0;160     };161 162     function ensureCapacity(minCapacity) {163         var oldCapacity = elementData.length;164         if (minCapacity > oldCapacity) {165             var oldData = elementData;166             var newCapacity = parseInt((oldCapacity * 3) / 2 + 1);167             if (newCapacity < minCapacity) {168                 newCapacity = minCapacity;169             }170             elementData = new Array(newCapacity);171             for (var i = 0; i < oldCapacity; i++) {172                 elementData[i] = oldData[i];173             }174         }175     }176 };