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11 package org.eclipse.core.internal.registry;
12
13 import java.io.*;
14
15
18
19 public final class HashtableOfInt {
20 private int[] keyTable;
21 private int[] valueTable;
22 private static final float GROWTH_FACTOR = 1.33f;
23
24 private int elementSize; private int threshold;
26
27 public HashtableOfInt() {
28 this(13);
29 }
30
31 public HashtableOfInt(int size) {
32 this.elementSize = 0;
33 this.threshold = size; int extraRoom = (int) (size * 1.33f);
35 if (this.threshold == extraRoom)
36 extraRoom++;
37 this.keyTable = new int[extraRoom];
38 this.valueTable = new int[extraRoom];
39 }
40
41 public boolean containsKey(int key) {
42 int index = key % valueTable.length;
43 int currentKey;
44 while ((currentKey = keyTable[index]) != 0) {
45 if (currentKey == key)
46 return true;
47 index = (index + 1) % keyTable.length;
48 }
49 return false;
50 }
51
52 public int get(int key) {
53 int index = key % valueTable.length;
54 int currentKey;
55 while ((currentKey = keyTable[index]) != 0) {
56 if (currentKey == key)
57 return valueTable[index];
58 index = (index + 1) % keyTable.length;
59 }
60 return Integer.MIN_VALUE;
61 }
62
63 public int removeKey(int key) {
64 int index = key % valueTable.length;
65 int currentKey;
66 while ((currentKey = keyTable[index]) != 0) {
67 if (currentKey == key) {
68 return valueTable[index];
69 }
70 index = (index + 1) % keyTable.length;
71 }
72 return Integer.MIN_VALUE;
73 }
74
75 public int put(int key, int value) {
76 int index = key % valueTable.length;
77 int currentKey;
78 while ((currentKey = keyTable[index]) != 0) {
79 if (currentKey == key)
80 return valueTable[index] = value;
81 index = (index + 1) % keyTable.length;
82 }
83 keyTable[index] = key;
84 valueTable[index] = value;
85
86 if (++elementSize > threshold)
88 rehash();
89 return value;
90 }
91
92 private void rehash() {
93 HashtableOfInt newHashtable = new HashtableOfInt((int) (elementSize * GROWTH_FACTOR)); int currentKey;
95 for (int i = keyTable.length; --i >= 0;)
96 if ((currentKey = keyTable[i]) != 0)
97 newHashtable.put(currentKey, valueTable[i]);
98
99 this.keyTable = newHashtable.keyTable;
100 this.valueTable = newHashtable.valueTable;
101 this.threshold = newHashtable.threshold;
102 }
103
104 public int size() {
105 return elementSize;
106 }
107
108 public String  toString() {
109 String s = ""; int object;
111 for (int i = 0, length = valueTable.length; i < length; i++)
112 if ((object = valueTable[i]) != Integer.MIN_VALUE)
113 s += keyTable[i] + " -> " + object + "\n"; return s;
115 }
116
117 public void save(DataOutputStream out) throws IOException {
118 out.writeInt(elementSize);
119 int tableSize = keyTable.length;
120 out.writeInt(tableSize);
121 out.writeInt(threshold);
122 for (int i = 0; i < tableSize; i++) {
123 out.writeInt(keyTable[i]);
124 out.writeInt(valueTable[i]);
125 }
126 }
127
128 public void load(DataInputStream in) throws IOException {
129 elementSize = in.readInt();
130 int tableSize = in.readInt();
131 threshold = in.readInt();
132 boolean fastMode = true;
133 if (((double) tableSize / elementSize) < GROWTH_FACTOR) {
134 keyTable = new int[(int) (elementSize * GROWTH_FACTOR)];
135 valueTable = new int[(int) (elementSize * GROWTH_FACTOR)];
136 elementSize = 0;
137 fastMode = false;
138 } else {
139 keyTable = new int[tableSize];
140 valueTable = new int[tableSize];
141 }
142 for (int i = 0; i < tableSize; i++) {
143 int key = in.readInt();
144 int value = in.readInt();
145 if (fastMode) {
146 keyTable[i] = key;
147 valueTable[i] = value;
148 } else {
149 put(key, value);
150 }
151 }
152 }
153 }
154 |
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