1 /*
2 * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package org.xml.sax.helpers;
27
28 import org.xml.sax.Attributes;
29
30
31 /**
32 * Default implementation of the Attributes interface.
33 *
34 * <p>This class provides a default implementation of the SAX2
35 * {@link org.xml.sax.Attributes Attributes} interface, with the
36 * addition of manipulators so that the list can be modified or
37 * reused.</p>
38 *
39 * <p>There are two typical uses of this class:</p>
40 *
41 * <ol>
42 * <li>to take a persistent snapshot of an Attributes object
43 * in a {@link org.xml.sax.ContentHandler#startElement startElement} event; or</li>
44 * <li>to construct or modify an Attributes object in a SAX2 driver or filter.</li>
45 * </ol>
46 *
47 * <p>This class replaces the now-deprecated SAX1 {@link
48 * org.xml.sax.helpers.AttributeListImpl AttributeListImpl}
49 * class; in addition to supporting the updated Attributes
50 * interface rather than the deprecated {@link org.xml.sax.AttributeList
51 * AttributeList} interface, it also includes a much more efficient
52 * implementation using a single array rather than a set of Vectors.</p>
53 *
54 * @since 1.4, SAX 2.0
55 * @author David Megginson
56 */
57 public class AttributesImpl implements Attributes
58 {
59
60
61 ////////////////////////////////////////////////////////////////////
62 // Constructors.
63 ////////////////////////////////////////////////////////////////////
64
65
66 /**
67 * Construct a new, empty AttributesImpl object.
68 */
69 public AttributesImpl ()
70 {
71 length = 0;
72 data = null;
73 }
74
75
76 /**
77 * Copy an existing Attributes object.
78 *
79 * <p>This constructor is especially useful inside a
80 * {@link org.xml.sax.ContentHandler#startElement startElement} event.</p>
81 *
82 * @param atts The existing Attributes object.
83 */
84 public AttributesImpl (Attributes atts)
85 {
86 setAttributes(atts);
87 }
88
89
90
91 ////////////////////////////////////////////////////////////////////
92 // Implementation of org.xml.sax.Attributes.
93 ////////////////////////////////////////////////////////////////////
94
95
96 /**
97 * Return the number of attributes in the list.
98 *
99 * @return The number of attributes in the list.
100 * @see org.xml.sax.Attributes#getLength
101 */
102 public int getLength ()
103 {
104 return length;
105 }
106
107
108 /**
109 * Return an attribute's Namespace URI.
110 *
111 * @param index The attribute's index (zero-based).
112 * @return The Namespace URI, the empty string if none is
113 * available, or null if the index is out of range.
114 * @see org.xml.sax.Attributes#getURI
115 */
116 public String getURI (int index)
117 {
118 if (index >= 0 && index < length) {
119 return data[index*5];
120 } else {
121 return null;
122 }
123 }
124
125
126 /**
127 * Return an attribute's local name.
128 *
129 * @param index The attribute's index (zero-based).
130 * @return The attribute's local name, the empty string if
131 * none is available, or null if the index if out of range.
132 * @see org.xml.sax.Attributes#getLocalName
133 */
134 public String getLocalName (int index)
135 {
136 if (index >= 0 && index < length) {
137 return data[index*5+1];
138 } else {
139 return null;
140 }
141 }
142
143
144 /**
145 * Return an attribute's qualified (prefixed) name.
146 *
147 * @param index The attribute's index (zero-based).
148 * @return The attribute's qualified name, the empty string if
149 * none is available, or null if the index is out of bounds.
150 * @see org.xml.sax.Attributes#getQName
151 */
152 public String getQName (int index)
153 {
154 if (index >= 0 && index < length) {
155 return data[index*5+2];
156 } else {
157 return null;
158 }
159 }
160
161
162 /**
163 * Return an attribute's type by index.
164 *
165 * @param index The attribute's index (zero-based).
166 * @return The attribute's type, "CDATA" if the type is unknown, or null
167 * if the index is out of bounds.
168 * @see org.xml.sax.Attributes#getType(int)
169 */
170 public String getType (int index)
171 {
172 if (index >= 0 && index < length) {
173 return data[index*5+3];
174 } else {
175 return null;
176 }
177 }
178
179
180 /**
181 * Return an attribute's value by index.
182 *
183 * @param index The attribute's index (zero-based).
184 * @return The attribute's value or null if the index is out of bounds.
185 * @see org.xml.sax.Attributes#getValue(int)
186 */
187 public String getValue (int index)
188 {
189 if (index >= 0 && index < length) {
190 return data[index*5+4];
191 } else {
192 return null;
193 }
194 }
195
196
197 /**
198 * Look up an attribute's index by Namespace name.
199 *
200 * <p>In many cases, it will be more efficient to look up the name once and
201 * use the index query methods rather than using the name query methods
202 * repeatedly.</p>
203 *
204 * @param uri The attribute's Namespace URI, or the empty
205 * string if none is available.
206 * @param localName The attribute's local name.
207 * @return The attribute's index, or -1 if none matches.
208 * @see org.xml.sax.Attributes#getIndex(java.lang.String,java.lang.String)
209 */
210 public int getIndex (String uri, String localName)
211 {
212 int max = length * 5;
213 for (int i = 0; i < max; i += 5) {
214 if (data[i].equals(uri) && data[i+1].equals(localName)) {
215 return i / 5;
216 }
217 }
218 return -1;
219 }
220
221
222 /**
223 * Look up an attribute's index by qualified (prefixed) name.
224 *
225 * @param qName The qualified name.
226 * @return The attribute's index, or -1 if none matches.
227 * @see org.xml.sax.Attributes#getIndex(java.lang.String)
228 */
229 public int getIndex (String qName)
230 {
231 int max = length * 5;
232 for (int i = 0; i < max; i += 5) {
233 if (data[i+2].equals(qName)) {
234 return i / 5;
235 }
236 }
237 return -1;
238 }
239
240
241 /**
242 * Look up an attribute's type by Namespace-qualified name.
243 *
244 * @param uri The Namespace URI, or the empty string for a name
245 * with no explicit Namespace URI.
246 * @param localName The local name.
247 * @return The attribute's type, or null if there is no
248 * matching attribute.
249 * @see org.xml.sax.Attributes#getType(java.lang.String,java.lang.String)
250 */
251 public String getType (String uri, String localName)
252 {
253 int max = length * 5;
254 for (int i = 0; i < max; i += 5) {
255 if (data[i].equals(uri) && data[i+1].equals(localName)) {
256 return data[i+3];
257 }
258 }
259 return null;
260 }
261
262
263 /**
264 * Look up an attribute's type by qualified (prefixed) name.
265 *
266 * @param qName The qualified name.
267 * @return The attribute's type, or null if there is no
268 * matching attribute.
269 * @see org.xml.sax.Attributes#getType(java.lang.String)
270 */
271 public String getType (String qName)
272 {
273 int max = length * 5;
274 for (int i = 0; i < max; i += 5) {
275 if (data[i+2].equals(qName)) {
276 return data[i+3];
277 }
278 }
279 return null;
280 }
281
282
283 /**
284 * Look up an attribute's value by Namespace-qualified name.
285 *
286 * @param uri The Namespace URI, or the empty string for a name
287 * with no explicit Namespace URI.
288 * @param localName The local name.
289 * @return The attribute's value, or null if there is no
290 * matching attribute.
291 * @see org.xml.sax.Attributes#getValue(java.lang.String,java.lang.String)
292 */
293 public String getValue (String uri, String localName)
294 {
295 int max = length * 5;
296 for (int i = 0; i < max; i += 5) {
297 if (data[i].equals(uri) && data[i+1].equals(localName)) {
298 return data[i+4];
299 }
300 }
301 return null;
302 }
303
304
305 /**
306 * Look up an attribute's value by qualified (prefixed) name.
307 *
308 * @param qName The qualified name.
309 * @return The attribute's value, or null if there is no
310 * matching attribute.
311 * @see org.xml.sax.Attributes#getValue(java.lang.String)
312 */
313 public String getValue (String qName)
314 {
315 int max = length * 5;
316 for (int i = 0; i < max; i += 5) {
317 if (data[i+2].equals(qName)) {
318 return data[i+4];
319 }
320 }
321 return null;
322 }
323
324
325
326 ////////////////////////////////////////////////////////////////////
327 // Manipulators.
328 ////////////////////////////////////////////////////////////////////
329
330
331 /**
332 * Clear the attribute list for reuse.
333 *
334 * <p>Note that little memory is freed by this call:
335 * the current array is kept so it can be
336 * reused.</p>
337 */
338 public void clear ()
339 {
340 if (data != null) {
341 for (int i = 0; i < (length * 5); i++)
342 data [i] = null;
343 }
344 length = 0;
345 }
346
347
348 /**
349 * Copy an entire Attributes object.
350 *
351 * <p>It may be more efficient to reuse an existing object
352 * rather than constantly allocating new ones.</p>
353 *
354 * @param atts The attributes to copy.
355 */
356 public void setAttributes (Attributes atts)
357 {
358 clear();
359 length = atts.getLength();
360 if (length > 0) {
361 data = new String[length*5];
362 for (int i = 0; i < length; i++) {
363 data[i*5] = atts.getURI(i);
364 data[i*5+1] = atts.getLocalName(i);
365 data[i*5+2] = atts.getQName(i);
366 data[i*5+3] = atts.getType(i);
367 data[i*5+4] = atts.getValue(i);
368 }
369 }
370 }
371
372
373 /**
374 * Add an attribute to the end of the list.
375 *
376 * <p>For the sake of speed, this method does no checking
377 * to see if the attribute is already in the list: that is
378 * the responsibility of the application.</p>
379 *
380 * @param uri The Namespace URI, or the empty string if
381 * none is available or Namespace processing is not
382 * being performed.
383 * @param localName The local name, or the empty string if
384 * Namespace processing is not being performed.
385 * @param qName The qualified (prefixed) name, or the empty string
386 * if qualified names are not available.
387 * @param type The attribute type as a string.
388 * @param value The attribute value.
389 */
390 public void addAttribute (String uri, String localName, String qName,
391 String type, String value)
392 {
393 ensureCapacity(length+1);
394 data[length*5] = uri;
395 data[length*5+1] = localName;
396 data[length*5+2] = qName;
397 data[length*5+3] = type;
398 data[length*5+4] = value;
399 length++;
400 }
401
402
403 /**
404 * Set an attribute in the list.
405 *
406 * <p>For the sake of speed, this method does no checking
407 * for name conflicts or well-formedness: such checks are the
408 * responsibility of the application.</p>
409 *
410 * @param index The index of the attribute (zero-based).
411 * @param uri The Namespace URI, or the empty string if
412 * none is available or Namespace processing is not
413 * being performed.
414 * @param localName The local name, or the empty string if
415 * Namespace processing is not being performed.
416 * @param qName The qualified name, or the empty string
417 * if qualified names are not available.
418 * @param type The attribute type as a string.
419 * @param value The attribute value.
420 * @exception java.lang.ArrayIndexOutOfBoundsException When the
421 * supplied index does not point to an attribute
422 * in the list.
423 */
424 public void setAttribute (int index, String uri, String localName,
425 String qName, String type, String value)
426 {
427 if (index >= 0 && index < length) {
428 data[index*5] = uri;
429 data[index*5+1] = localName;
430 data[index*5+2] = qName;
431 data[index*5+3] = type;
432 data[index*5+4] = value;
433 } else {
434 badIndex(index);
435 }
436 }
437
438
439 /**
440 * Remove an attribute from the list.
441 *
442 * @param index The index of the attribute (zero-based).
443 * @exception java.lang.ArrayIndexOutOfBoundsException When the
444 * supplied index does not point to an attribute
445 * in the list.
446 */
447 public void removeAttribute (int index)
448 {
449 if (index >= 0 && index < length) {
450 if (index < length - 1) {
451 System.arraycopy(data, (index+1)*5, data, index*5,
452 (length-index-1)*5);
453 }
454 index = (length - 1) * 5;
455 data [index++] = null;
456 data [index++] = null;
457 data [index++] = null;
458 data [index++] = null;
459 data [index] = null;
460 length--;
461 } else {
462 badIndex(index);
463 }
464 }
465
466
467 /**
468 * Set the Namespace URI of a specific attribute.
469 *
470 * @param index The index of the attribute (zero-based).
471 * @param uri The attribute's Namespace URI, or the empty
472 * string for none.
473 * @exception java.lang.ArrayIndexOutOfBoundsException When the
474 * supplied index does not point to an attribute
475 * in the list.
476 */
477 public void setURI (int index, String uri)
478 {
479 if (index >= 0 && index < length) {
480 data[index*5] = uri;
481 } else {
482 badIndex(index);
483 }
484 }
485
486
487 /**
488 * Set the local name of a specific attribute.
489 *
490 * @param index The index of the attribute (zero-based).
491 * @param localName The attribute's local name, or the empty
492 * string for none.
493 * @exception java.lang.ArrayIndexOutOfBoundsException When the
494 * supplied index does not point to an attribute
495 * in the list.
496 */
497 public void setLocalName (int index, String localName)
498 {
499 if (index >= 0 && index < length) {
500 data[index*5+1] = localName;
501 } else {
502 badIndex(index);
503 }
504 }
505
506
507 /**
508 * Set the qualified name of a specific attribute.
509 *
510 * @param index The index of the attribute (zero-based).
511 * @param qName The attribute's qualified name, or the empty
512 * string for none.
513 * @exception java.lang.ArrayIndexOutOfBoundsException When the
514 * supplied index does not point to an attribute
515 * in the list.
516 */
517 public void setQName (int index, String qName)
518 {
519 if (index >= 0 && index < length) {
520 data[index*5+2] = qName;
521 } else {
522 badIndex(index);
523 }
524 }
525
526
527 /**
528 * Set the type of a specific attribute.
529 *
530 * @param index The index of the attribute (zero-based).
531 * @param type The attribute's type.
532 * @exception java.lang.ArrayIndexOutOfBoundsException When the
533 * supplied index does not point to an attribute
534 * in the list.
535 */
536 public void setType (int index, String type)
537 {
538 if (index >= 0 && index < length) {
539 data[index*5+3] = type;
540 } else {
541 badIndex(index);
542 }
543 }
544
545
546 /**
547 * Set the value of a specific attribute.
548 *
549 * @param index The index of the attribute (zero-based).
550 * @param value The attribute's value.
551 * @exception java.lang.ArrayIndexOutOfBoundsException When the
552 * supplied index does not point to an attribute
553 * in the list.
554 */
555 public void setValue (int index, String value)
556 {
557 if (index >= 0 && index < length) {
558 data[index*5+4] = value;
559 } else {
560 badIndex(index);
561 }
562 }
563
564
565
566 ////////////////////////////////////////////////////////////////////
567 // Internal methods.
568 ////////////////////////////////////////////////////////////////////
569
570
571 /**
572 * Ensure the internal array's capacity.
573 *
574 * @param n The minimum number of attributes that the array must
575 * be able to hold.
576 */
577 private void ensureCapacity (int n) {
578 if (n <= 0) {
579 return;
580 }
581 int max;
582 if (data == null || data.length == 0) {
583 max = 25;
584 }
585 else if (data.length >= n * 5) {
586 return;
587 }
588 else {
589 max = data.length;
590 }
591 while (max < n * 5) {
592 max *= 2;
593 }
594
595 String newData[] = new String[max];
596 if (length > 0) {
597 System.arraycopy(data, 0, newData, 0, length*5);
598 }
599 data = newData;
600 }
601
602
603 /**
604 * Report a bad array index in a manipulator.
605 *
606 * @param index The index to report.
607 * @exception java.lang.ArrayIndexOutOfBoundsException Always.
608 */
609 private void badIndex (int index)
610 throws ArrayIndexOutOfBoundsException
611 {
612 String msg =
613 "Attempt to modify attribute at illegal index: " + index;
614 throw new ArrayIndexOutOfBoundsException(msg);
615 }
616
617
618
619 ////////////////////////////////////////////////////////////////////
620 // Internal state.
621 ////////////////////////////////////////////////////////////////////
622
623 int length;
624 String data [];
625
626 }
627
628 // end of AttributesImpl.java