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1
19
24
25 package org.netbeans.core.output2;
26
27 import java.lang.ref.WeakReference  ;
28 import java.util.Arrays ;
29
30
37 class PairMap {
38
40 private String [] keys = new String [10];
41
42 Object [] vals = new Object [10];
43 int last = -1;
44 private boolean weak = false;
45
46
47 PairMap() {
48 }
49
50 public synchronized void clear() {
51 keys = new String [10];
52 vals = new Object [10];
53 last = -1;
54 }
55
56 public synchronized int size() {
57 if (weak) {
58 return prune();
59 } else {
60 return last+1;
61 }
62 }
63
64 public synchronized boolean isEmpty() {
65 return size() == 0;
66 }
67
68 public synchronized void setWeak(boolean val) {
69 if (weak != val) {
70 weak = val;
71 for (int i=0; i <= last; i++) {
72 if (weak) {
73 vals[i] = new WeakReference (vals[i]);
74 } else {
75 vals[i] = ((WeakReference ) vals[i]).get();
76 }
77 }
78 if (!weak) {
79 prune();
80 }
81 }
82 }
83
84 public synchronized void add (String key, NbIO value) {
85 if (last == keys.length -1) {
86 growArrays();
87 }
88 last++;
89 keys[last] = key;
90 vals[last] = value;
91 }
92
93 public synchronized NbIO get (String key, boolean mustBeClosed) {
94 if (last < 0) {
95 return null;
96 }
97 boolean foundNull = false;
98 for (int i=last; i >= 0; i--) {
99 if (keys[i].equals(key)) {
100 NbIO io = getValue(i);
101 foundNull |= io == null;
102 if (io != null && (!mustBeClosed || (mustBeClosed && io.isStreamClosed()))) {
103 return io;
104 }
105 }
106 }
107 if (foundNull) {
108 prune();
109 }
110 return null;
111 }
112
113 public boolean containsValue(NbIO io) {
114 if (last < 0) {
115 return false;
116 }
117 for (int i=last; i >= 0; i--) {
118 if (getValue(i) == io) {
119 return true;
120 }
121 }
122 return false;
123 }
124
125 public synchronized NbIO get (String key) {
126 return get(key, false);
127 }
128
129 public synchronized String remove (NbIO io) {
130 int idx = indexOfVal (io);
131 if (idx == -1) {
132 return null;
133 }
134 String result = keys[idx];
135 removeIndex(idx);
136 return result;
137 }
138
139 public synchronized NbIO remove (String key) {
140 int idx = indexOfKey(key);
141 if (idx == -1) {
142 return null;
143 }
144 NbIO result = getValue(idx);
145 removeIndex(idx);
146 return result;
147 }
148
149 private NbIO getValue(int idx) {
150 if (idx > last) {
151 throw new ArrayIndexOutOfBoundsException ("Tried to fetch item " + idx + " but map only contains " + (last + 1) + " elements"); }
154 NbIO result;
155 Object o = vals[idx];
156 if (weak) {
157 result = (NbIO) ((WeakReference ) vals[idx]).get();
158 if (result == null && !pruning) {
159 removeIndex(idx);
160 }
161
162 } else {
163 result = (NbIO) o;
164 }
165 return result;
166 }
167
168 public void setValue (int idx, NbIO value) {
169 if (weak) {
170 vals[idx] = new WeakReference (value);
171 } else {
172 vals[idx] = value;
173 }
174 }
175
176 private void removeIndex (int idx) {
177 if (idx < 0 || idx > last) {
178 throw new ArrayIndexOutOfBoundsException ("Trying to remove " + "element " + idx + " but map only contains " + (last+1) + " elements"); }
182 if (idx == last) {
183 keys[idx] = null;
184 vals[idx] = null;
185 } else {
186 keys[idx] = keys[last];
187 vals[idx] = vals[last];
188 vals[last] = null;
189 keys[last] = null;
190 }
191 last--;
192 }
193
194 private int indexOfKey (String key) {
195 for (int i=last; i >= 0; i--) {
196 if (keys[i].equals(key)) {
197 return i;
198 }
199 }
200 return -1;
201 }
202
203 private int indexOfVal (NbIO val) {
204 for (int i=last; i >= 0; i--) {
205 if (vals[i] == val) {
206 return i;
207 }
208 }
209 return -1;
210 }
211
212 private void growArrays() {
213 String [] newKeys = new String [keys.length * 2];
214 NbIO[] newVals = new NbIO[vals.length * 2];
215 System.arraycopy (keys, 0, newKeys, 0, last+1);
216 System.arraycopy (vals, 0, newVals, 0, last+1);
217 keys = newKeys;
218 vals = newVals;
219 }
220
221 private boolean pruning = false;
222 private int prune() {
223 pruning = true;
224 int oldSize = last + 1;
225 int result = oldSize;
226 int[] removes = new int[oldSize];
227 Arrays.fill (removes, -1);
228 for (int i=last; i >= 0; i--) {
229 if (getValue(i) == null) {
230 removes[i] = i;
231 result--;
232 }
233 }
234
235 if (result != oldSize) {
236 for (int i=removes.length-1; i >= 0; i--) {
237 if (removes[i] != -1) {
238 removeIndex(removes[i]);
239 }
240 }
241 }
242 pruning = false;
243 return result;
244 }
245
246 }
247 |
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