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21 package au.id.jericho.lib.html;
22
23 import java.util.*;
24
25
28 final class IntStringHashMap {
29 private static final int DEFAULT_INITIAL_CAPACITY=15;
30 private static final float DEFAULT_LOAD_FACTOR=0.75f;
31 private transient Entry[] entries; private transient int size;
33 private int threshold;
34 private float loadFactor;
35 private int bitmask;
37 public IntStringHashMap(int initialCapacity, final float loadFactor) {
38 this.loadFactor=loadFactor;
39 int capacity=1;
40 while (capacity<initialCapacity) capacity<<=1;
41 threshold=(int)(capacity*loadFactor);
42 entries=new Entry[capacity];
43 bitmask=capacity-1;
44 }
45
46 public IntStringHashMap(final int initialCapacity) {
47 this(initialCapacity,DEFAULT_LOAD_FACTOR);
48 }
49
50 public IntStringHashMap() {
51 this(DEFAULT_INITIAL_CAPACITY,DEFAULT_LOAD_FACTOR);
52 }
53
54 public int size() {
55 return size;
56 }
57
58 public boolean isEmpty() {
59 return size==0;
60 }
61
62 private int getIndex(final int key) {
63 return key&bitmask; }
65
66 public String  get(final int key) {
67 Entry entry=entries[getIndex(key)];
68 while (entry!=null) {
69 if (key==entry.key) return entry.value;
70 entry=entry.next;
71 }
72 return null;
73 }
74
75 private Entry getEntry(final int key) {
76 Entry entry=entries[getIndex(key)];
77 while (entry!=null && key!=entry.key) entry=entry.next;
78 return entry;
79 }
80
81 public boolean containsKey(final int key) {
82 return getEntry(key)!=null;
83 }
84
85 public String put(final int key, final String value) {
86 final int index=getIndex(key);
87 for (Entry entry=entries[index]; entry!= null; entry=entry.next) {
88 if (key==entry.key) {
89 final String oldValue=entry.value;
90 entry.value=value;
91 return oldValue;
92 }
93 }
94 entries[index]=new Entry(key,value,entries[index]);
95 if (size++>=threshold) increaseCapacity();
96 return null;
97 }
98
99 private void increaseCapacity() {
100 final int oldCapacity=entries.length;
101 final Entry[] oldEntries=entries;
102 entries=new Entry[oldCapacity<<1];
103 bitmask=entries.length-1;
104 for (int i=0; i<oldCapacity; i++) {
105 Entry entry=oldEntries[i];
106 while (entry!=null) {
107 final Entry next=entry.next;
108 final int index=getIndex(entry.key);
109 entry.next=entries[index];
110 entries[index]=entry;
111 entry=next;
112 }
113 }
114 threshold=(int)(entries.length*loadFactor);
115 }
116
117 public String remove(final int key) {
118 final int index=getIndex(key);
119 Entry previous=null;
120 for (Entry entry=entries[index]; entry!=null; entry=(previous=entry).next) {
121 if (key==entry.key) {
122 if (previous==null)
123 entries[index]=entry.next;
124 else
125 previous.next=entry.next;
126 size--;
127 return entry.value;
128 }
129 }
130 return null;
131 }
132
133 public void clear() {
134 for (int i=bitmask; i>=0; i--) entries[i]=null;
135 size=0;
136 }
137
138 public boolean containsValue(final String value) {
139 if (value==null) {
140 for (int i=bitmask; i>=0; i--)
141 for (Entry entry=entries[i]; entry!=null; entry=entry.next)
142 if (entry.value==null) return true;
143 } else {
144 for (int i=bitmask; i>=0; i--)
145 for (Entry entry=entries[i]; entry!=null; entry=entry.next)
146 if (value.equals(entry.value)) return true;
147 }
148 return false;
149 }
150
151 private static final class Entry {
152 final int key;
153 String value;
154 Entry next;
155
156 public Entry(final int key, final String value, final Entry next) {
157 this.key=key;
158 this.value=value;
159 this.next=next;
160 }
161 }
162 }
163 |
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