1
2
3/**//**********************************************************
4* JavaScript实现的ArrayList类
5*
6* @author {yangl}
7* @version $Revision: 0.5 $ $Date: 2008/04/02 15:00:00 $
8* @description
9* Method:
10* add(element);
11* addElementAt(index, element);
12* contains(element);
13* get(index);
14* isEmpty(index);
15* indexOf(element);
16* lastIndexOf(element);
17* remove()
18* setElementAt(index, element);
19* size();
20* toString();
21* @example
22* var arrList = new ArrayList();
23* //var arrList = new ArrayList(10);
24* arrList.add("000");
25* arrList.add("001");
26* arrList.add("002");
27*
28*********************************************************/
29// JavaScript ArrayList
 30/**//**
31Method:
32        add(element);
33        addElementAt(index, element);
34        contains(element);
35        get(index);
36        isEmpty(index);
37        indexOf(element);
38        lastIndexOf(element);
39        remove(index);
40        setElementAt(index, element);
41        size();
42        toString();
43*/
44/**//**
45Example:
46        var arrList = new ArrayList();
47        //var arrList = new ArrayList(10);
48        arrList.add("000");
49        arrList.add("001");
50        arrList.add("002");
51*/
52var ArrayList = function () {
53    var args = ArrayList.arguments;
54    var initialCapacity = 10;
55
56    if (args != null && args.length > 0) {
57        initialCapacity = args[0];
58    }
59
60    var elementData = new Array(initialCapacity);
61    var elementCount = 0;
62
63    this.size = function () {
64        return elementCount;
65    };
66
67    this.add = function (element) {
68        //alert("add");
 69        ensureCapacity(elementCount + 1);
70        elementData[elementCount++] = element;
71        return true;
72    };
73
74    this.addElementAt = function (index, element) {
75        //alert("addElementAt");
 76        if (index > elementCount || index < 0) {
77            alert("IndexOutOfBoundsException, Index: " + index + ", Size: " + elementCount);
78            return;
79            //throw (new Error(-1,"IndexOutOfBoundsException, Index: "+index+", Size: " + elementCount));
 80        }
81        ensureCapacity(elementCount + 1);
82        for (var i = elementCount + 1; i > index; i--) {
83            elementData[i] = elementData[i - 1];
84        }
85        elementData[index] = element;
86        elementCount++;
87    };
88
89    this.setElementAt = function (index, element) {
90        //alert("setElementAt");
 91        if (index > elementCount || index < 0) {
92            alert("IndexOutOfBoundsException, Index: " + index + ", Size: " + elementCount);
93            return;
94            //throw (new Error(-1,"IndexOutOfBoundsException, Index: "+index+", Size: " + elementCount));
 95        }
96        elementData[index] = element;
97    };
98
99    this.toString = function () {
100        //alert("toString()");
101        var str = "{";
102        for (var i = 0; i < elementCount; i++) {
103            if (i > 0) {
104                str += ",";
105            }
106            str += elementData[i];
107        }
108        str += "}";
109        return str;
110    };
111
112    this.get = function (index) {
113        //alert("elementAt");
114        if (index >= elementCount) {
115            alert("ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount);
116            return;
117            //throw ( new Error( -1,"ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount ) );
118        }
119        return elementData[index];
120    };
121
122    this.remove = function (index) {
123        if (index >= elementCount) {
124            alert("ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount);
125            //return;
126            throw (new Error(-1, "ArrayIndexOutOfBoundsException, " + index + " >= " + elementCount));
127        }
128        var oldData = elementData[index];
129        for (var i = index; i < elementCount - 1; i++) {
130            elementData[i] = elementData[i + 1];
131        }
132        elementData[elementCount - 1] = null;
133        elementCount--;
134        return oldData;
135    };
136
137    this.isEmpty = function () {
138        return elementCount == 0;
139    };
140
141    this.indexOf = function (elem) {
142        //alert("indexOf");
143        for (var i = 0; i < elementCount; i++) {
144            if (elementData[i] == elem) {
145                return i;
146            }
147        }
148        return -1;
149    };
150
151    this.lastIndexOf = function (elem) {
152        for (var i = elementCount - 1; i >= 0; i--) {
153            if (elementData[i] == elem) {
154                return i;
155            }
156        }
157        return -1;
158    };
159
160    this.contains = function (elem) {
161        return this.indexOf(elem) >= 0;
162    };
163
164    function ensureCapacity(minCapacity) {
165        var oldCapacity = elementData.length;
166        if (minCapacity > oldCapacity) {
167            var oldData = elementData;
168            var newCapacity = parseInt((oldCapacity * 3) / 2 + 1);
169            if (newCapacity < minCapacity) {
170                newCapacity = minCapacity;
171            }
172            elementData = new Array(newCapacity);
173            for (var i = 0; i < oldCapacity; i++) {
174                elementData[i] = oldData[i];
175            }
176        }
177    }
178};
179