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1
29
30 package com.caucho.db.table;
31
32 import com.caucho.db.index.BTree;
33 import com.caucho.db.index.KeyCompare;
34 import com.caucho.db.index.StringKeyCompare;
35 import com.caucho.db.sql.Expr;
36 import com.caucho.db.sql.QueryContext;
37 import com.caucho.db.sql.SelectResult;
38 import com.caucho.db.store.Transaction;
39 import com.caucho.util.L10N;
40
41 import java.sql.SQLException  ;
42 import java.util.logging.Level ;
43 import java.util.logging.Logger ;
44
45 class StringColumn extends Column {
46 private static final Logger log
47 = Logger.getLogger(StringColumn.class.getName());
48 private static final L10N L = new L10N(StringColumn.class);
49
50 private final int _maxLength;
51
52
58 StringColumn(Row row, String name, int maxLength)
59 {
60 super(row, name);
61
62 if (maxLength < 0)
63 throw new IllegalArgumentException ("length must be non-negative");
64 else if (255 < maxLength)
65 throw new IllegalArgumentException ("length too big");
66
67 _maxLength = maxLength;
68 }
69
70
73 public int getTypeCode()
74 {
75 return VARCHAR;
76 }
77
78
81 public Class getJavaType()
82 {
83 return String .class;
84 }
85
86
89 public int getDeclarationSize()
90 {
91 return _maxLength;
92 }
93
94
97 public int getLength()
98 {
99 return 2 * _maxLength + 1;
100 }
101
102
105 public KeyCompare getIndexKeyCompare()
106 {
107 return new StringKeyCompare();
108 }
109
110
117 void setString(Transaction xa, byte []block, int rowOffset, String str)
118 {
119 int startOffset = rowOffset + _columnOffset;
120
121 if (str == null) {
122 setNull(block, rowOffset);
123 return;
124 }
125
126 int len = str.length();
127 int offset = startOffset + 1;
128 int maxOffset = offset + 2 * _maxLength;
129
130 for (int i = 0; i < len && offset < maxOffset; i++) {
131 int ch = str.charAt(i);
132
133 block[offset++] = (byte) (ch >> 8);
134 block[offset++] = (byte) (ch);
135 }
136
137 block[startOffset] = (byte) (len);
138 setNonNull(block, rowOffset);
139 }
140
141 public String getString(byte []block, int rowOffset)
142 {
143 if (isNull(block, rowOffset))
144 return null;
145
146 int startOffset = rowOffset + _columnOffset;
147 int len = block[startOffset] & 0xff;
148
149 char []cBuf = new char[len];
150 StringBuffer cb = new StringBuffer ();
151
152 int offset = startOffset + 1;
153 int endOffset = offset + 2 * len;
154 int i = 0;
155 while (offset < endOffset) {
156 int ch1 = block[offset++] & 0xff;
157 int ch2 = block[offset++] & 0xff;
158
159 cBuf[i++] = (char) ((ch1 << 8) + ch2);
160 }
161
162 return new String (cBuf, 0, cBuf.length);
163 }
164
165
172 void setExpr(Transaction xa,
173 byte []block, int rowOffset,
174 Expr expr, QueryContext context)
175 throws SQLException
176 {
177 if (expr.isNull(null))
178 setNull(block, rowOffset);
179 else
180 setString(xa, block, rowOffset, expr.evalString(context));
181 }
182
183
186 public boolean isEqual(byte []block1, int rowOffset1,
187 byte []block2, int rowOffset2)
188 {
189 if (isNull(block1, rowOffset1) != isNull(block2, rowOffset2))
190 return false;
191
192 int startOffset1 = rowOffset1 + _columnOffset;
193 int len1 = block1[startOffset1] & 0xff;
194
195 int startOffset2 = rowOffset2 + _columnOffset;
196 int len2 = block2[startOffset2] & 0xff;
197
198 if (len1 != len2)
199 return false;
200
201 for (int i = 2 * len1; i > 0; i--) {
202 if (block1[startOffset1 + i] != block2[startOffset2 + i])
203 return false;
204 }
205
206 return true;
207 }
208
209
212 public boolean isEqual(byte []block, int rowOffset,
213 byte []buffer, int offset, int length)
214 {
215 if (isNull(block, rowOffset))
216 return false;
217
218 int startOffset = rowOffset + _columnOffset;
219 int len = block[startOffset] & 0xff;
220
221 if (len != length)
222 return false;
223
224 int blockOffset = startOffset + 1;
225 int endOffset = blockOffset + 2 * len;
226 while (blockOffset < endOffset) {
227 if (block[blockOffset++] != buffer[offset++])
228 return false;
229 }
230
231 return true;
232 }
233
234 public boolean isEqual(byte []block, int rowOffset, String value)
235 {
236 if (value == null)
237 return isNull(block, rowOffset);
238 else if (isNull(block, rowOffset))
239 return false;
240
241 int startOffset = rowOffset + _columnOffset;
242 int len = block[startOffset] & 0xff;
243
244 int strLength = value.length();
245 int strOffset = 0;
246
247 int offset = startOffset + 1;
248 int endOffset = offset + 2 * len;
249 while (offset < endOffset && strOffset < strLength) {
250 int ch1 = ((block[offset++] & 0xff) << 8) + (block[offset++] & 0xff);
251 char ch = value.charAt(strOffset++);
252
253 if (ch1 != ch)
254 return false;
255 }
256
257 return offset == endOffset && strOffset == strLength;
258 }
259
260
263 public void evalToResult(byte []block, int rowOffset, SelectResult result)
264 {
265 if (isNull(block, rowOffset)) {
266 result.writeNull();
267 return;
268 }
269
270 int startOffset = rowOffset + _columnOffset;
271 int len = block[startOffset] & 0xff;
272
273 result.writeString(block, startOffset + 1, len);
274
282 }
283
284
294 int evalToBuffer(byte []block, int rowOffset,
295 byte []buffer, int bufferOffset)
296 throws SQLException
297 {
298 if (isNull(block, rowOffset))
299 return 0;
300
301 int startOffset = rowOffset + _columnOffset;
302 int len = getLength();
304
305 System.arraycopy(block, startOffset, buffer, bufferOffset, len);
306
307 return len;
308 }
309
310
317 void setIndex(Transaction xa,
318 byte []block, int rowOffset,
319 long rowAddr, QueryContext context)
320 throws SQLException
321 {
322 BTree index = getIndex();
323
324 if (index != null) {
325 try {
326 index.insert(block,
327 rowOffset + _columnOffset, getLength(),
328 rowAddr,
329 xa,
330 false);
331 } catch (SQLException e) {
332 log.log(Level.FINER, e.toString(), e);
333
334 throw new SQLException (L.l("StringColumn '{0}.{1}' unique index set failed for {2}",
335 getTable().getName(),
336 getName(),
337 getString(block, rowOffset)));
338 }
339 }
340 }
341
342
349 void delete(Transaction xa, byte []block, int rowOffset)
350 throws SQLException
351 {
352 BTree index = getIndex();
353
354 if (index != null)
355 index.remove(block, rowOffset + _columnOffset, getLength(), xa);
356 }
357
358 public String toString()
359 {
360 if (getIndex() != null)
361 return "StringColumn[" + getName() + ",index]";
362 else
363 return "StringColumn[" + getName() + "]";
364 }
365 }
366 |
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