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1
11 package org.eclipse.jdt.internal.core.util;
12
13
16 public final class HashtableOfArrayToObject implements Cloneable  {
17
18 public Object [][] keyTable;
20 public Object [] valueTable;
21
22 public int elementSize; int threshold;
24
25 public HashtableOfArrayToObject() {
26 this(13);
27 }
28
29 public HashtableOfArrayToObject(int size) {
30
31 this.elementSize = 0;
32 this.threshold = size; int extraRoom = (int) (size * 1.75f);
34 if (this.threshold == extraRoom)
35 extraRoom++;
36 this.keyTable = new Object [extraRoom][];
37 this.valueTable = new Object [extraRoom];
38 }
39
40 public Object clone() throws CloneNotSupportedException {
41 HashtableOfArrayToObject result = (HashtableOfArrayToObject) super.clone();
42 result.elementSize = this.elementSize;
43 result.threshold = this.threshold;
44
45 int length = this.keyTable.length;
46 result.keyTable = new Object [length][];
47 System.arraycopy(this.keyTable, 0, result.keyTable, 0, length);
48
49 length = this.valueTable.length;
50 result.valueTable = new Object [length];
51 System.arraycopy(this.valueTable, 0, result.valueTable, 0, length);
52 return result;
53 }
54
55 public boolean containsKey(Object [] key) {
56 int length = this.keyTable.length;
57 int index = hashCode(key) % length;
58 int keyLength = key.length;
59 Object [] currentKey;
60 while ((currentKey = this.keyTable[index]) != null) {
61 if (currentKey.length == keyLength && Util.equalArraysOrNull(currentKey, key))
62 return true;
63 if (++index == length) {
64 index = 0;
65 }
66 }
67 return false;
68 }
69
70 public Object get(Object [] key) {
71 int length = this.keyTable.length;
72 int index = hashCode(key) % length;
73 int keyLength = key.length;
74 Object [] currentKey;
75 while ((currentKey = this.keyTable[index]) != null) {
76 if (currentKey.length == keyLength && Util.equalArraysOrNull(currentKey, key))
77 return this.valueTable[index];
78 if (++index == length) {
79 index = 0;
80 }
81 }
82 return null;
83 }
84
85 public Object [] getKey(Object [] key, int keyLength) {
86 int length = this.keyTable.length;
87 int index = hashCode(key, keyLength) % length;
88 Object [] currentKey;
89 while ((currentKey = this.keyTable[index]) != null) {
90 if (currentKey.length == keyLength && Util.equalArrays(currentKey, key, keyLength))
91 return currentKey;
92 if (++index == length) {
93 index = 0;
94 }
95 }
96 return null;
97 }
98
99 private int hashCode(Object [] element) {
100 return hashCode(element, element.length);
101 }
102
103 private int hashCode(Object [] element, int length) {
104 int hash = 0;
105 for (int i = length-1; i >= 0; i--)
106 hash = Util.combineHashCodes(hash, element[i].hashCode());
107 return hash & 0x7FFFFFFF;
108 }
109
110 public Object put(Object [] key, Object value) {
111 int length = this.keyTable.length;
112 int index = hashCode(key) % length;
113 int keyLength = key.length;
114 Object [] currentKey;
115 while ((currentKey = this.keyTable[index]) != null) {
116 if (currentKey.length == keyLength && Util.equalArraysOrNull(currentKey, key))
117 return this.valueTable[index] = value;
118 if (++index == length) {
119 index = 0;
120 }
121 }
122 this.keyTable[index] = key;
123 this.valueTable[index] = value;
124
125 if (++this.elementSize > threshold)
127 rehash();
128 return value;
129 }
130
131 public Object removeKey(Object [] key) {
132 int length = this.keyTable.length;
133 int index = hashCode(key) % length;
134 int keyLength = key.length;
135 Object [] currentKey;
136 while ((currentKey = this.keyTable[index]) != null) {
137 if (currentKey.length == keyLength && Util.equalArraysOrNull(currentKey, key)) {
138 Object value = this.valueTable[index];
139 this.elementSize--;
140 this.keyTable[index] = null;
141 this.valueTable[index] = null;
142 rehash();
143 return value;
144 }
145 if (++index == length) {
146 index = 0;
147 }
148 }
149 return null;
150 }
151
152 private void rehash() {
153
154 HashtableOfArrayToObject newHashtable = new HashtableOfArrayToObject(elementSize * 2); Object [] currentKey;
156 for (int i = this.keyTable.length; --i >= 0;)
157 if ((currentKey = this.keyTable[i]) != null)
158 newHashtable.put(currentKey, this.valueTable[i]);
159
160 this.keyTable = newHashtable.keyTable;
161 this.valueTable = newHashtable.valueTable;
162 this.threshold = newHashtable.threshold;
163 }
164
165 public int size() {
166 return elementSize;
167 }
168
169 public String toString() {
170 StringBuffer buffer = new StringBuffer ();
171 Object [] element;
172 for (int i = 0, length = this.keyTable.length; i < length; i++)
173 if ((element = this.keyTable[i]) != null) {
174 buffer.append('{');
175 for (int j = 0, length2 = element.length; j < length2; j++) {
176 buffer.append(element[j]);
177 if (j != length2-1)
178 buffer.append(", "); }
180 buffer.append("} -> "); buffer.append(this.valueTable[i]);
182 if (i != length-1)
183 buffer.append('\n');
184 }
185 return buffer.toString();
186 }
187 }
188 |
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