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1
23
24 package com.sun.ejb.containers.util;
25
26 import java.io.*;
27 import java.util.*;
28 import java.util.ArrayList  ;
29 import java.security.*;
30
31
32 public class LongHashMap {
33
34 protected static final int DEFAULT_CAPACITY = 128;
35 protected static final float DEFAULT_LOAD_FACTOR = 0.75f;
36 protected static final int MAXIMUM_CAPACITY = 1 << 30;
37
38 protected static boolean debug = false;
39
40 protected transient Entry[] table;
41 protected float loadFactor;
42 protected transient int size;
43 protected int bucketmask;
44 protected int capacity;
45 protected int threshold;
46
47 public LongHashMap() {
48 this(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR);
49 }
50
51 public LongHashMap(int initialCapacity) {
52 this(initialCapacity, DEFAULT_LOAD_FACTOR);
53 }
54
55 public LongHashMap(int initialCapacity, float loadFactor) {
56 if (initialCapacity > MAXIMUM_CAPACITY) {
57 initialCapacity = MAXIMUM_CAPACITY;
58 }
59 if (loadFactor <= 0 || Float.isNaN(loadFactor)) {
60 throw new IllegalArgumentException ("Illegal load factor: "
61 + loadFactor);
62 }
63
64 capacity = 1;
66
67 while (capacity < initialCapacity) {
68 capacity <<= 1;
69 }
70 this.loadFactor = loadFactor;
71 this.threshold = (int)(capacity * loadFactor);
72 this.table = new Entry[capacity];
73 this.bucketmask = capacity - 1;
74 }
75
76
77 public boolean contains(long key) {
78 int index = ((int) key) & bucketmask;
79 for (Entry e = table[index]; e != null; e = e.next) {
80 if (e.key == key) {
81 return true;
82 }
83 }
84 return false;
85 }
86
87 public Object get(long key) {
88 int index = ((int) key) & bucketmask;
89 for (Entry e = table[index]; e != null; e = e.next) {
90 if (e.key == key) {
91 return e.value;
92 }
93 }
94 return null;
95 }
96
97 public Object put(long key, Object value) {
98 int index = ((int) key) & bucketmask;
99
100 for (Entry e = table[index]; e != null; e = e.next) {
101 if (e.key == key) {
102 Object oldValue = e.value;
103 e.value = value;
104 return oldValue;
105 }
106 }
107
108 table[index] = new Entry(key, value, table[index]);
109 if (size++ >= threshold) {
110 int newCapacity = 2 * capacity;
111 Entry[] newTable = new Entry[newCapacity];
112 transfer(newTable);
113 table = newTable;
114 capacity = newCapacity;
115 threshold = (int)(newCapacity * loadFactor);
116 bucketmask = capacity-1;
117 }
118 return null;
119 }
120
121
124 private void transfer(Entry[] newTable) {
125 Entry[] src = table;
126 int newCapacity = newTable.length;
127 int bucketmask = newCapacity-1;
128 for (int j = 0; j < src.length; j++) {
129 Entry e = src[j];
130 if (e != null) {
131 src[j] = null;
132 do {
133 Entry next = e.next;
134 int index = ((int) e.key) & bucketmask;
135 e.next = newTable[index];
136 newTable[index] = e;
137 e = next;
138 } while (e != null);
139 }
140 }
141 }
142
143 public Object remove(long key) {
144 int index = ((int) key) & bucketmask;
145 Entry prev = table[index];
146 Entry e = prev;
147
148 while (e != null) {
149 Entry next = e.next;
150 if (e.key == key) {
151 size--;
152 if (prev == e) {
153 table[index] = next;
154 } else {
155 prev.next = next;
156 }
157 return e.value;
158 }
159 prev = e;
160 e = next;
161 }
162
163 return null;
164 }
165
166 public Enumeration elements() {
167 Vector keyList = new Vector();
168 for (int index=0; index<capacity; index++) {
169 for (Entry e = table[index]; e != null; e = e.next) {
170 keyList.addElement(e.value);
171 }
172 }
173
174 return keyList.elements();
175 }
176
177 public Iterator values() {
178 ArrayList keyList = new ArrayList ();
179 for (int index=0; index<capacity; index++) {
180 for (Entry e = table[index]; e != null; e = e.next) {
181 keyList.add(e.value);
182 }
183 }
184
185 return keyList.iterator();
186 }
187
188 public Iterator keys() {
189 ArrayList keyList = new ArrayList ();
190 for (int index=0; index<capacity; index++) {
191 for (Entry e = table[index]; e != null; e = e.next) {
192 keyList.add(new Long (e.key));
193 }
194 }
195
196 return keyList.iterator();
197 }
198
199 static class Entry {
200 final long key;
201 Object value;
202 Entry next;
203
204
207 Entry(long k, Object v, Entry n) {
208 key = k;
209 value = v;
210 next = n;
211 }
212
213 public int hashCode() {
214 return ((int) key);
215 }
216
217 public String toString() {
218 return key + "=" + value;
219 }
220 }
221 }
222 |
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