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1
28
29 package com.caucho.relaxng.program;
30
31 import com.caucho.relaxng.RelaxException;
32 import com.caucho.util.CharBuffer;
33 import com.caucho.util.L10N;
34 import com.caucho.xml.QName;
35
36 import java.util.ArrayList  ;
37 import java.util.HashSet ;
38 import java.util.Iterator ;
39 import java.util.NoSuchElementException ;
40
41
44 public class GroupItem extends Item {
45 protected final static L10N L = new L10N(GroupItem.class);
46
47 private Item _first;
48 private Item _second;
49
50 private GroupItem(Item first, Item second)
51 {
52 _first = first;
53 _second = second;
54 }
55
56 public static Item create(Item first, Item second)
57 {
58 if (first == null || second == null)
59 return null;
60 else if (first instanceof EmptyItem)
61 return second;
62 else if (second instanceof EmptyItem)
63 return first;
64 else if (first instanceof GroupItem) {
65 GroupItem firstSeq = (GroupItem) first;
66
67 return create(firstSeq.getFirst(), create(firstSeq.getSecond(), second));
68 }
69 else if (first instanceof InElementItem) {
70 InElementItem firstElt = (InElementItem) first;
71
72 return InElementItem.create(firstElt.getFirst(),
73 create(firstElt.getSecond(), second));
74 }
75 else
76 return new GroupItem(first, second);
77 }
78
79 Item getFirst()
80 {
81 return _first;
82 }
83
84 Item getSecond()
85 {
86 return _second;
87 }
88
89
92 public void firstSet(HashSet <QName> set)
93 {
94 _first.firstSet(set);
95 if (_first.allowEmpty())
96 _second.firstSet(set);
97 }
98
99
102 public void requiredFirstSet(HashSet <QName> set)
103 {
104 if (! _first.allowEmpty())
105 _first.requiredFirstSet(set);
106 else
107 _second.requiredFirstSet(set);
108 }
109
110
113 public Iterator <Item> getItemsIterator()
114 {
115 if ( _first == null && _second == null )
116 return emptyItemIterator();
117
118 return new Iterator <Item>() {
119 private int _cnt;
120
121 public boolean hasNext()
122 {
123 if (_cnt == 0)
124 return _first != null || _second != null;
125 else if (_cnt == 1)
126 return _first != null && _second != null;
127 else
128 return false;
129 }
130
131 public Item next()
132 {
133 if (!hasNext())
134 throw new NoSuchElementException ();
135
136 if (_cnt++ == 0)
137 return _first != null ? _first : _second;
138 else
139 return _second;
140 }
141
142 public void remove()
143 {
144 throw new UnsupportedOperationException ();
145 }
146 };
147 }
148
149
150
158 public Item startElement(QName name)
159 throws RelaxException
160 {
161 Item nextHead = _first.startElement(name);
162
163 Item tail = GroupItem.create(nextHead, _second);
164
165 if (_first.allowEmpty())
166 return ChoiceItem.create(tail, _second.startElement(name));
167 else
168 return tail;
169 }
170
171
178 public Item text(String string)
179 throws RelaxException
180 {
181 Item nextHead = _first.text(string);
182
183 Item tail = GroupItem.create(nextHead, _second);
184
185 if (_first.allowEmpty())
186 return ChoiceItem.create(tail, _second.text(string));
187 else
188 return tail;
189 }
190
191
194 public void attributeSet(HashSet <QName> set)
195 {
196 _first.attributeSet(set);
197 _second.attributeSet(set);
198 }
199
200
208 public boolean allowAttribute(QName name, String value)
209 throws RelaxException
210 {
211 return (_first.allowAttribute(name, value) ||
212 _second.allowAttribute(name, value));
213 }
214
215
223 public Item setAttribute(QName name, String value)
224 throws RelaxException
225 {
226 Item first = _first.setAttribute(name, value);
227 Item second = _second.setAttribute(name, value);
228
229 if (first == _first && second == _second)
230 return this;
231 else if (first == null)
232 return second;
233 else if (second == null)
234 return first;
235 else
236 return create(first, second);
237 }
238
239
242 public Item attributeEnd()
243 {
244 Item first = _first.attributeEnd();
245 Item second = _second.attributeEnd();
246
247 if (first == null || second == null)
248 return null;
249 else if (first == _first && second == _second)
250 return this;
251 else
252 return create(first, second);
253 }
254
255
258 public boolean allowEmpty()
259 {
260 return _first.allowEmpty() && _second.allowEmpty();
261 }
262
263
272 public boolean allowsElement(QName name)
273 {
274 return _first.allowsElement(name) || _second.allowsElement(name);
275 }
276
277
280 public String toSyntaxDescription(int depth)
281 {
282 if (_second instanceof EmptyItem)
283 return _first.toSyntaxDescription(depth);
284
285 ArrayList <Item> items = new ArrayList <Item>();
286
287 Item item = this;
288 while (item instanceof GroupItem) {
289 GroupItem groupItem = (GroupItem) item;
290
291 items.add(groupItem._first);
292
293 item = groupItem._second;
294 }
295
296 if (item != null && ! (item instanceof EmptyItem))
297 items.add(item);
298
299 CharBuffer cb = CharBuffer.allocate();
300
301 cb.append('(');
302
303 boolean isSimple = true;
304 for (int i = 0; i < items.size(); i++) {
305 item = items.get(i);
306
307 if (i == 0) {
308 cb.append(item.toSyntaxDescription(depth + 1));
309 isSimple = item.isSimpleSyntax();
310 }
311 else
312 isSimple = addSyntaxItem(cb, item, depth, isSimple);
313
314 if (i + 1 < items.size()) {
315 Item next = items.get(i + 1);
316
317 if (next instanceof ZeroOrMoreItem) {
318 ZeroOrMoreItem starItem = (ZeroOrMoreItem) next;
319
320 if (starItem.getItem().equals(item)) {
321 cb.append("+");
322 i++;
323
324 if (i == 1 && i == items.size() - 1) {
325 cb.delete(0, 1);
326
327 return cb.close();
328 }
329 }
330 }
331 }
332 }
333
334 cb.append(')');
335
336 return cb.close();
337 }
338
339
342 private boolean addSyntaxItem(CharBuffer cb, Item item,
343 int depth, boolean isSimple)
344 {
345 if (! item.isSimpleSyntax())
346 isSimple = false;
347
348 if (isSimple) {
349 cb.append(", ");
350 }
351 else {
352 cb.append(",");
353 addSyntaxNewline(cb, depth + 1);
354 }
355
356 cb.append(item.toSyntaxDescription(depth + 1));
357
358 return isSimple;
359 }
360
361
364 protected boolean isSimpleSyntax()
365 {
366 return (_second instanceof EmptyItem) && _first.isSimpleSyntax();
367 }
368
369
372 public int hashCode()
373 {
374 return _first.hashCode() * 65521 + _second.hashCode();
375 }
376
377
380 public boolean equals(Object o)
381 {
382 if (! (o instanceof GroupItem))
383 return false;
384
385 GroupItem seq = (GroupItem) o;
386
387 return _first.equals(seq._first) && _second.equals(seq._second);
388 }
389
390 public String toString()
391 {
392 return "GroupItem[" + _first + ", " + _second + "]";
393 }
394 }
395
396 |
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