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1
11 package org.eclipse.jdt.internal.core.util;
12
13
16 public final class HashSetOfArray implements Cloneable  {
17
18 public Object [][] set;
20
21 public int elementSize; int threshold;
23
24 public HashSetOfArray() {
25 this(13);
26 }
27
28 public HashSetOfArray(int size) {
29
30 this.elementSize = 0;
31 this.threshold = size; int extraRoom = (int) (size * 1.75f);
33 if (this.threshold == extraRoom)
34 extraRoom++;
35 this.set = new Object [extraRoom][];
36 }
37
38 public Object clone() throws CloneNotSupportedException {
39 HashSetOfArray result = (HashSetOfArray) super.clone();
40 result.elementSize = this.elementSize;
41 result.threshold = this.threshold;
42
43 int length = this.set.length;
44 result.set = new Object [length][];
45 System.arraycopy(this.set, 0, result.set, 0, length);
46
47 return result;
48 }
49
50 public boolean contains(Object [] array) {
51 int length = this.set.length;
52 int index = hashCode(array) % length;
53 int arrayLength = array.length;
54 Object [] currentArray;
55 while ((currentArray = this.set[index]) != null) {
56 if (currentArray.length == arrayLength && Util.equalArraysOrNull(currentArray, array))
57 return true;
58 if (++index == length) {
59 index = 0;
60 }
61 }
62 return false;
63 }
64
65 private int hashCode(Object [] element) {
66 return hashCode(element, element.length);
67 }
68
69 private int hashCode(Object [] element, int length) {
70 int hash = 0;
71 for (int i = length-1; i >= 0; i--)
72 hash = Util.combineHashCodes(hash, element[i].hashCode());
73 return hash & 0x7FFFFFFF;
74 }
75
76 public Object add(Object [] array) {
77 int length = this.set.length;
78 int index = hashCode(array) % length;
79 int arrayLength = array.length;
80 Object [] currentArray;
81 while ((currentArray = this.set[index]) != null) {
82 if (currentArray.length == arrayLength && Util.equalArraysOrNull(currentArray, array))
83 return this.set[index] = array;
84 if (++index == length) {
85 index = 0;
86 }
87 }
88 this.set[index] = array;
89
90 if (++this.elementSize > threshold)
92 rehash();
93 return array;
94 }
95
96 public Object remove(Object [] array) {
97 int length = this.set.length;
98 int index = hashCode(array) % length;
99 int arrayLength = array.length;
100 Object [] currentArray;
101 while ((currentArray = this.set[index]) != null) {
102 if (currentArray.length == arrayLength && Util.equalArraysOrNull(currentArray, array)) {
103 Object existing = this.set[index];
104 this.elementSize--;
105 this.set[index] = null;
106 rehash();
107 return existing;
108 }
109 if (++index == length) {
110 index = 0;
111 }
112 }
113 return null;
114 }
115
116 private void rehash() {
117
118 HashSetOfArray newHashSet = new HashSetOfArray(elementSize * 2); Object [] currentArray;
120 for (int i = this.set.length; --i >= 0;)
121 if ((currentArray = this.set[i]) != null)
122 newHashSet.add(currentArray);
123
124 this.set = newHashSet.set;
125 this.threshold = newHashSet.threshold;
126 }
127
128 public int size() {
129 return elementSize;
130 }
131
132 public String toString() {
133 StringBuffer buffer = new StringBuffer ();
134 Object [] element;
135 for (int i = 0, length = this.set.length; i < length; i++)
136 if ((element = this.set[i]) != null) {
137 buffer.append('{');
138 for (int j = 0, length2 = element.length; j < length2; j++) {
139 buffer.append(element[j]);
140 if (j != length2-1)
141 buffer.append(", "); }
143 buffer.append("}"); if (i != length-1)
145 buffer.append('\n');
146 }
147 return buffer.toString();
148 }
149 }
150 |
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