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21 package org.jacorb.collection.util;
22
23 import java.util.*;
24
25 public class DynArray
26 {
27 protected Object  elementData[];
28 protected int elementCount = 0;
29 public DynArray(int initialCapacity) {
30 this.elementData = ArrayFactory.get_array( initialCapacity );
31 }
32 public DynArray() {
33 this.elementData = new Object [16];
34 }
35 public void copyInto(Object anArray[]) {
36 System.arraycopy( elementData, 0, anArray, 0, elementCount );
37 }
38
39 public void ensureCapacity(int minCapacity) {
40 if (minCapacity > elementData.length) {
41 ensureCapacityHelper(minCapacity);
42 }
43 }
44
45 private void ensureCapacityHelper(int minCapacity) {
46 Object [] oldData = elementData;
47 elementData = ArrayFactory.get_array( minCapacity );
48 System.arraycopy(oldData, 0, elementData, 0, elementCount);
49 ArrayFactory.free_array( oldData );
50 }
51
52 public void setSize(int newSize) {
53 if (newSize > elementCount) {
54 if (newSize > elementData.length) {
55 ensureCapacityHelper(newSize);
56 }
57 for (int i = newSize ; i >= elementCount ;) {
58 elementData[--i] = null;
59 }
60 } else {
61 for(int i = newSize; i<elementCount; i++ ){
62 elementData[i] = null;
63 }
64 }
65 elementCount = newSize;
66 }
67
68 public int capacity() {
69 return elementData.length;
70 }
71
72 public int size() {
73 return elementCount;
74 }
75
76 public boolean isEmpty() {
77 return elementCount == 0;
78 }
79
80 public Enumeration elements() {
81 return new DynArrayEnumerator(this);
82 }
83
84 public boolean contains(Object elem) {
85 return indexOf(elem, 0) >= 0;
86 }
87
88 public int indexOf(Object elem) {
89 return indexOf(elem, 0);
90 }
91
92 public int indexOf(Object elem, int index) {
93 if (index >= elementCount) {
94 throw new ArrayIndexOutOfBoundsException (index);
95 }
96 for (int i = index ; i < elementCount ; i++) {
97 if (elem.equals(elementData[i])) {
98 return i;
99 }
100 }
101 return -1;
102 }
103
104 public Object elementAt(int index) {
105 return elementData[index];
106 }
107
108 public void setElementAt(Object obj, int index) {
109 if (index >= elementCount) {
110 throw new ArrayIndexOutOfBoundsException (index + " >= " +
111 elementCount);
112 }
113 elementData[index] = obj;
114 }
115
116 public void removeElementAt(int index) {
117 if (index >= elementCount || index < 0) {
118 throw new ArrayIndexOutOfBoundsException (index);
119 }
120 int j = elementCount - index - 1;
121 if (j > 0) {
122 System.arraycopy(elementData, index + 1, elementData, index, j);
123 }
124 elementCount--;
125 elementData[elementCount] = null;
126 }
127
128 public void insertElementAt(Object obj, int index) {
129 int newcount = elementCount + 1;
130 if (index >= newcount) {
131 throw new ArrayIndexOutOfBoundsException (index);
132 }
133 if (newcount > elementData.length) {
134 ensureCapacityHelper(newcount);
135 }
136 System.arraycopy(elementData, index, elementData, index + 1, elementCount - index);
137 elementData[index] = obj;
138 elementCount++;
139 }
140
141 public void addElement(Object obj) {
142 int newcount = elementCount + 1;
143 if (newcount > elementData.length) {
144 ensureCapacityHelper(newcount);
145 }
146 elementData[elementCount++] = obj;
147 }
148
149 public boolean removeElement(Object obj) {
150 int i = indexOf(obj);
151 if (i >= 0) {
152 removeElementAt(i);
153 return true;
154 }
155 return false;
156 }
157
158 public void removeAllElements() {
159 for (int i = 0; i < elementCount; i++) {
160 elementData[i] = null;
161 }
162 elementCount = 0;
163 }
164
165 public Object firstElement() {
166 if (elementCount == 0) {
167 throw new NoSuchElementException();
168 }
169 return elementData[0];
170 }
171
172 public Object lastElement() {
173 if (elementCount == 0) {
174 throw new NoSuchElementException();
175 }
176 return elementData[elementCount - 1];
177 }
178
179 protected void finalize(){
180 if( elementData != null ){
181 ArrayFactory.free_array( elementData );
182 }
183 }
184 }
185
186 final
187 class DynArrayEnumerator implements java.util.Enumeration {
188 Object [] data;
189 int count;
190 int elementCount;
191 DynArrayEnumerator(DynArray da) {
192 data = ArrayFactory.get_array( da.elementCount );
193 elementCount = da.elementCount;
194 System.arraycopy(da.elementData, 0, data, 0, da.elementCount );
195 count = 0;
196 }
197
198 public boolean hasMoreElements() {
199 return count < elementCount;
200 }
201
202 public Object nextElement() {
203 if (count < elementCount) {
204 return data[count++];
205 }
206 if( data != null ){
207 ArrayFactory.free_array( data );
208 }
209 throw new NoSuchElementException("DynArrayEnumerator");
210 }
211 protected void finalize(){
212 if( data != null ){
213 ArrayFactory.free_array( data );
214 }
215 }
216 }
217
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