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1
11 package org.eclipse.jdt.internal.compiler.util;
12
13 import org.eclipse.jdt.core.compiler.CharOperation;
14
15
18 public final class HashtableOfIntValues implements Cloneable  {
19
20 public static final int NO_VALUE = Integer.MIN_VALUE;
21
22 public char[] keyTable[];
24 public int valueTable[];
25
26 public int elementSize; int threshold;
28
29 public HashtableOfIntValues() {
30 this(13);
31 }
32
33 public HashtableOfIntValues(int size) {
34
35 this.elementSize = 0;
36 this.threshold = size; int extraRoom = (int) (size * 1.75f);
38 if (this.threshold == extraRoom)
39 extraRoom++;
40 this.keyTable = new char[extraRoom][];
41 this.valueTable = new int[extraRoom];
42 }
43
44 public Object clone() throws CloneNotSupportedException {
45 HashtableOfIntValues result = (HashtableOfIntValues) super.clone();
46 result.elementSize = this.elementSize;
47 result.threshold = this.threshold;
48
49 int length = this.keyTable.length;
50 result.keyTable = new char[length][];
51 System.arraycopy(this.keyTable, 0, result.keyTable, 0, length);
52
53 length = this.valueTable.length;
54 result.valueTable = new int[length];
55 System.arraycopy(this.valueTable, 0, result.valueTable, 0, length);
56 return result;
57 }
58
59 public boolean containsKey(char[] key) {
60 int length = keyTable.length,
61 index = CharOperation.hashCode(key) % length;
62 int keyLength = key.length;
63 char[] currentKey;
64 while ((currentKey = keyTable[index]) != null) {
65 if (currentKey.length == keyLength && CharOperation.equals(currentKey, key))
66 return true;
67 if (++index == length) {
68 index = 0;
69 }
70 }
71 return false;
72 }
73
74 public int get(char[] key) {
75 int length = keyTable.length,
76 index = CharOperation.hashCode(key) % length;
77 int keyLength = key.length;
78 char[] currentKey;
79 while ((currentKey = keyTable[index]) != null) {
80 if (currentKey.length == keyLength && CharOperation.equals(currentKey, key))
81 return valueTable[index];
82 if (++index == length) {
83 index = 0;
84 }
85 }
86 return NO_VALUE;
87 }
88
89 public int put(char[] key, int value) {
90 int length = keyTable.length,
91 index = CharOperation.hashCode(key) % length;
92 int keyLength = key.length;
93 char[] currentKey;
94 while ((currentKey = keyTable[index]) != null) {
95 if (currentKey.length == keyLength && CharOperation.equals(currentKey, key))
96 return valueTable[index] = value;
97 if (++index == length) {
98 index = 0;
99 }
100 }
101 keyTable[index] = key;
102 valueTable[index] = value;
103
104 if (++elementSize > threshold)
106 rehash();
107 return value;
108 }
109
110 public int removeKey(char[] key) {
111 int length = keyTable.length,
112 index = CharOperation.hashCode(key) % length;
113 int keyLength = key.length;
114 char[] currentKey;
115 while ((currentKey = keyTable[index]) != null) {
116 if (currentKey.length == keyLength && CharOperation.equals(currentKey, key)) {
117 int value = valueTable[index];
118 elementSize--;
119 keyTable[index] = null;
120 valueTable[index] = NO_VALUE;
121 rehash();
122 return value;
123 }
124 if (++index == length) {
125 index = 0;
126 }
127 }
128 return NO_VALUE;
129 }
130
131 private void rehash() {
132
133 HashtableOfIntValues newHashtable = new HashtableOfIntValues(elementSize * 2); char[] currentKey;
135 for (int i = keyTable.length; --i >= 0;)
136 if ((currentKey = keyTable[i]) != null)
137 newHashtable.put(currentKey, valueTable[i]);
138
139 this.keyTable = newHashtable.keyTable;
140 this.valueTable = newHashtable.valueTable;
141 this.threshold = newHashtable.threshold;
142 }
143
144 public int size() {
145 return elementSize;
146 }
147
148 public String toString() {
149 String s = ""; char[] key;
151 for (int i = 0, length = valueTable.length; i < length; i++)
152 if ((key = keyTable[i]) != null)
153 s += new String (key) + " -> " + valueTable[i] + "\n"; return s;
155 }
156 }
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