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1
65
66
67 package org.hsqldb;
68
69 import java.io.IOException  ;
70
71 import org.hsqldb.lib.IntLookup;
72 import org.hsqldb.rowio.RowInputInterface;
73 import org.hsqldb.rowio.RowOutputInterface;
74
75
79
94 class DiskNode extends Node {
95
96 protected Row rData;
97 private int iLeft = NO_POS;
98 private int iRight = NO_POS;
99 private int iParent = NO_POS;
100 private int iId; static final int SIZE_IN_BYTE = 4 * 4;
102
103 DiskNode(CachedRow r, RowInputInterface in,
104 int id) throws IOException , HsqlException {
105
106 iId = id;
107 rData = r;
108 iBalance = in.readIntData();
109 iLeft = in.readIntData();
110
111 if (iLeft <= 0) {
112 iLeft = NO_POS;
113 }
114
115 iRight = in.readIntData();
116
117 if (iRight <= 0) {
118 iRight = NO_POS;
119 }
120
121 iParent = in.readIntData();
122
123 if (iParent <= 0) {
124 iParent = NO_POS;
125 }
126
127 if (Trace.DOASSERT) {
128
129 }
135 }
136
137 DiskNode(CachedRow r, int id) {
138 iId = id;
139 rData = r;
140 }
141
142 void delete() {
143 rData = null;
144 iBalance = -2;
145 }
146
147 int getKey() {
148
149 if (rData != null) {
150 return ((CachedRow) rData).iPos;
151 }
152
153 return NO_POS;
154 }
155
156 Row getRow() throws HsqlException {
157
158 if (Trace.DOASSERT) {
159 Trace.doAssert(rData != null);
160 }
161
162 return rData;
163 }
164
165 private Node findNode(int pos) throws HsqlException {
166
167 Node ret = null;
168 Row r = ((CachedRow) rData).getTable().getRow(pos);
169
170 if (r != null) {
171 ret = r.getNode(iId);
172 }
173
174 return ret;
175 }
176
177 boolean isLeft(Node node) throws HsqlException {
178
179 if (node == null) {
180 return iLeft == NO_POS;
181 }
182
183 return iLeft == ((DiskNode) node).getKey();
184 }
185
186 boolean isRight(Node node) throws HsqlException {
187
188 if (node == null) {
189 return iRight == NO_POS;
190 }
191
192 return iRight == ((DiskNode) node).getKey();
193 }
194
195 Node getLeft() throws HsqlException {
196
197 if (Trace.DOASSERT) {
198 Trace.doAssert(iBalance != -2);
199 }
200
201 if (iLeft == NO_POS) {
202 return null;
203 }
204
205 return findNode(iLeft);
206 }
207
208 Node getRight() throws HsqlException {
209
210 if (Trace.DOASSERT) {
211 Trace.doAssert(iBalance != -2);
212 }
213
214 if (iRight == NO_POS) {
215 return null;
216 }
217
218 return findNode(iRight);
219 }
220
221 Node getParent() throws HsqlException {
222
223 if (Trace.DOASSERT) {
224 Trace.doAssert(iBalance != -2);
225 }
226
227 if (iParent == NO_POS) {
228 return null;
229 }
230
231 return findNode(iParent);
232 }
233
234 boolean isRoot() {
235 return iParent == Node.NO_POS;
236 }
237
238 boolean isFromLeft() throws HsqlException {
239
240 if (this.isRoot()) {
241 return true;
242 }
243
244 if (Trace.DOASSERT) {
245 Trace.doAssert(getParent() != null);
246 }
247
248 DiskNode parent = (DiskNode) getParent();
249
250 return getKey() == parent.iLeft;
251 }
252
253 Object [] getData() throws HsqlException {
254
255 if (Trace.DOASSERT) {
256 Trace.doAssert(iBalance != -2);
257 }
258
259 return rData.getData();
260 }
261
262 void setParent(Node n) throws HsqlException {
263
264 if (Trace.DOASSERT) {
265 Trace.doAssert(iBalance != -2);
266 }
267
268 ((CachedRow) rData).setChanged();
269
270 iParent = n == null ? NO_POS
271 : n.getKey();
272 }
273
274 void setBalance(int b) throws HsqlException {
275
276 if (Trace.DOASSERT) {
277 Trace.doAssert(iBalance != -2);
278 }
279
280 if (iBalance != b) {
281 ((CachedRow) rData).setChanged();
282
283 iBalance = b;
284 }
285 }
286
287 void setLeft(Node n) throws HsqlException {
288
289 if (Trace.DOASSERT) {
290 Trace.doAssert(iBalance != -2);
291 }
292
293 ((CachedRow) rData).setChanged();
294
295 iLeft = n == null ? NO_POS
296 : n.getKey();
297 }
298
299 void setRight(Node n) throws HsqlException {
300
301 if (Trace.DOASSERT) {
302 Trace.doAssert(iBalance != -2);
303 }
304
305 ((CachedRow) rData).setChanged();
306
307 iRight = n == null ? NO_POS
308 : n.getKey();
309 }
310
311 boolean equals(Node n) {
312
313
341 return this == n
342 || (n != null && getKey() == ((DiskNode) n).getKey());
343 }
344
345 void write(RowOutputInterface out) throws IOException {
346
347 if (Trace.DOASSERT) {
348
349 }
355
356 out.writeIntData(iBalance);
357 out.writeIntData((iLeft == NO_POS) ? 0
358 : iLeft);
359 out.writeIntData((iRight == NO_POS) ? 0
360 : iRight);
361 out.writeIntData((iParent == NO_POS) ? 0
362 : iParent);
363 }
364
365 Node getUpdatedNode() throws HsqlException {
366
367 Row row = rData.getUpdatedRow();
368
369 return row == null ? null
370 : row.getNode(iId);
371 }
372
373 void writeTranslate(RowOutputInterface out, IntLookup lookup) {
374
375 out.writeIntData(iBalance);
376 writeTranslatePointer(iLeft, out, lookup);
377 writeTranslatePointer(iRight, out, lookup);
378 writeTranslatePointer(iParent, out, lookup);
379 }
380
381 private void writeTranslatePointer(int pointer, RowOutputInterface out,
382 IntLookup lookup) {
383
384 int newPointer = 0;
385
386 if (pointer != Node.NO_POS) {
387 newPointer = lookup.lookupFirstEqual(pointer);
388 }
389
390 out.writeIntData(newPointer);
391 }
392 }
393 |
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