1 /*
2 * reserved comment block
3 * DO NOT REMOVE OR ALTER!
4 */
5 /*
6 * Licensed to the Apache Software Foundation (ASF) under one or more
7 * contributor license agreements. See the NOTICE file distributed with
8 * this work for additional information regarding copyright ownership.
9 * The ASF licenses this file to You under the Apache License, Version 2.0
10 * (the "License"); you may not use this file except in compliance with
11 * the License. You may obtain a copy of the License at
12 *
13 * http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
20 */
21
22 package com.sun.org.apache.xerces.internal.impl.dtd;
23
24 import com.sun.org.apache.xerces.internal.util.SymbolTable;
25 import com.sun.org.apache.xerces.internal.xni.Augmentations;
26 import com.sun.org.apache.xerces.internal.xni.XMLDTDContentModelHandler;
27 import com.sun.org.apache.xerces.internal.xni.XNIException;
28
29 /**
30 * <p>A DTD grammar that produces balanced syntax trees.</p>
31 *
32 * @xerces.internal
33 *
34 * @author Michael Glavassevich, IBM
35 */
36 final class BalancedDTDGrammar extends DTDGrammar {
37
38 //
39 // Data
40 //
41
42 /** Mixed. */
43 private boolean fMixed;
44
45 /** Stack depth */
46 private int fDepth = 0;
47
48 /** Children content model operation stack. */
49 private short [] fOpStack = null;
50
51 /** Holder for choice/sequence/leaf groups at each depth. */
52 private int [][] fGroupIndexStack;
53
54 /** Sizes of the allocated portions of each int[] in fGroupIndexStack. */
55 private int [] fGroupIndexStackSizes;
56
57 //
58 // Constructors
59 //
60
61 /** Default constructor. */
62 public BalancedDTDGrammar(SymbolTable symbolTable, XMLDTDDescription desc) {
63 super(symbolTable, desc);
64 } // BalancedDTDGrammar(SymbolTable,XMLDTDDescription)
65
66 //
67 // Public methods
68 //
69
70 /**
71 * The start of a content model. Depending on the type of the content
72 * model, specific methods may be called between the call to the
73 * startContentModel method and the call to the endContentModel method.
74 *
75 * @param elementName The name of the element.
76 * @param augs Additional information that may include infoset
77 * augmentations.
78 * @throws XNIException Thrown by handler to signal an error.
79 */
80 public final void startContentModel(String elementName, Augmentations augs)
81 throws XNIException {
82 fDepth = 0;
83 initializeContentModelStacks();
84 super.startContentModel(elementName, augs);
85 } // startContentModel(String)
86
87 /**
88 * A start of either a mixed or children content model. A mixed
89 * content model will immediately be followed by a call to the
90 * <code>pcdata()</code> method. A children content model will
91 * contain additional groups and/or elements.
92 *
93 * @param augs Additional information that may include infoset
94 * augmentations.
95 * @throws XNIException Thrown by handler to signal an error.
96 *
97 * @see #any
98 * @see #empty
99 */
100 public final void startGroup(Augmentations augs) throws XNIException {
101 ++fDepth;
102 initializeContentModelStacks();
103 fMixed = false;
104 } // startGroup()
105
106 /**
107 * The appearance of "#PCDATA" within a group signifying a
108 * mixed content model. This method will be the first called
109 * following the content model's <code>startGroup()</code>.
110 *
111 *@param augs Additional information that may include infoset
112 * augmentations.
113 *
114 * @throws XNIException Thrown by handler to signal an error.
115 *
116 * @see #startGroup
117 */
118 public final void pcdata(Augmentations augs) throws XNIException {
119 fMixed = true;
120 } // pcdata()
121
122 /**
123 * A referenced element in a mixed or children content model.
124 *
125 * @param elementName The name of the referenced element.
126 * @param augs Additional information that may include infoset
127 * augmentations.
128 *
129 * @throws XNIException Thrown by handler to signal an error.
130 */
131 public final void element(String elementName, Augmentations augs) throws XNIException {
132 addToCurrentGroup(addUniqueLeafNode(elementName));
133 } // element(String)
134
135 /**
136 * The separator between choices or sequences of a mixed or children
137 * content model.
138 *
139 * @param separator The type of children separator.
140 * @param augs Additional information that may include infoset
141 * augmentations.
142 * @throws XNIException Thrown by handler to signal an error.
143 *
144 * @see org.apache.xerces.xni.XMLDTDContentModelHandler#SEPARATOR_CHOICE
145 * @see org.apache.xerces.xni.XMLDTDContentModelHandler#SEPARATOR_SEQUENCE
146 */
147 public final void separator(short separator, Augmentations augs) throws XNIException {
148 if (separator == XMLDTDContentModelHandler.SEPARATOR_CHOICE) {
149 fOpStack[fDepth] = XMLContentSpec.CONTENTSPECNODE_CHOICE;
150 }
151 else if (separator == XMLDTDContentModelHandler.SEPARATOR_SEQUENCE) {
152 fOpStack[fDepth] = XMLContentSpec.CONTENTSPECNODE_SEQ;
153 }
154 } // separator(short)
155
156 /**
157 * The occurrence count for a child in a children content model or
158 * for the mixed content model group.
159 *
160 * @param occurrence The occurrence count for the last element
161 * or group.
162 * @param augs Additional information that may include infoset
163 * augmentations.
164 * @throws XNIException Thrown by handler to signal an error.
165 *
166 * @see org.apache.xerces.xni.XMLDTDContentModelHandler#OCCURS_ZERO_OR_ONE
167 * @see org.apache.xerces.xni.XMLDTDContentModelHandler#OCCURS_ZERO_OR_MORE
168 * @see org.apache.xerces.xni.XMLDTDContentModelHandler#OCCURS_ONE_OR_MORE
169 */
170 public final void occurrence(short occurrence, Augmentations augs) throws XNIException {
171 if (!fMixed) {
172 int currentIndex = fGroupIndexStackSizes[fDepth] - 1;
173 if (occurrence == XMLDTDContentModelHandler.OCCURS_ZERO_OR_ONE) {
174 fGroupIndexStack[fDepth][currentIndex] = addContentSpecNode(XMLContentSpec.CONTENTSPECNODE_ZERO_OR_ONE, fGroupIndexStack[fDepth][currentIndex], -1);
175 }
176 else if ( occurrence == XMLDTDContentModelHandler.OCCURS_ZERO_OR_MORE) {
177 fGroupIndexStack[fDepth][currentIndex] = addContentSpecNode(XMLContentSpec.CONTENTSPECNODE_ZERO_OR_MORE, fGroupIndexStack[fDepth][currentIndex], -1);
178 }
179 else if ( occurrence == XMLDTDContentModelHandler.OCCURS_ONE_OR_MORE) {
180 fGroupIndexStack[fDepth][currentIndex] = addContentSpecNode(XMLContentSpec.CONTENTSPECNODE_ONE_OR_MORE, fGroupIndexStack[fDepth][currentIndex], -1);
181 }
182 }
183 } // occurrence(short)
184
185 /**
186 * The end of a group for mixed or children content models.
187 *
188 * @param augs Additional information that may include infoset
189 * augmentations.
190 * @throws XNIException Thrown by handler to signal an error.
191 */
192 public final void endGroup(Augmentations augs) throws XNIException {
193 final int length = fGroupIndexStackSizes[fDepth];
194 final int group = length > 0 ? addContentSpecNodes(0, length - 1) : addUniqueLeafNode(null);
195 --fDepth;
196 addToCurrentGroup(group);
197 } // endGroup()
198
199 /**
200 * The end of the DTD.
201 *
202 * @param augs Additional information that may include infoset
203 * augmentations.
204 * @throws XNIException Thrown by handler to signal an error.
205 */
206 public final void endDTD(Augmentations augs) throws XNIException {
207 super.endDTD(augs);
208 fOpStack = null;
209 fGroupIndexStack = null;
210 fGroupIndexStackSizes = null;
211 } // endDTD()
212
213 //
214 // Protected methods
215 //
216
217 /**
218 * Adds the content spec to the given element declaration.
219 */
220 protected final void addContentSpecToElement(XMLElementDecl elementDecl) {
221 int contentSpec = fGroupIndexStackSizes[0] > 0 ? fGroupIndexStack[0][0] : -1;
222 setContentSpecIndex(fCurrentElementIndex, contentSpec);
223 }
224
225 //
226 // Private methods
227 //
228
229 /**
230 * Creates a subtree from the leaf nodes at the current depth.
231 */
232 private int addContentSpecNodes(int begin, int end) {
233 if (begin == end) {
234 return fGroupIndexStack[fDepth][begin];
235 }
236 final int middle = (begin + end) >>> 1;
237 return addContentSpecNode(fOpStack[fDepth],
238 addContentSpecNodes(begin, middle),
239 addContentSpecNodes(middle + 1, end));
240 } // addContentSpecNodes(int,int)
241
242 /**
243 * Initialize the stacks which temporarily hold content models.
244 */
245 private void initializeContentModelStacks() {
246 if (fOpStack == null) {
247 fOpStack = new short[8];
248 fGroupIndexStack = new int [8][];
249 fGroupIndexStackSizes = new int [8];
250 }
251 else if (fDepth == fOpStack.length) {
252 short [] newOpStack = new short[fDepth * 2];
253 System.arraycopy(fOpStack, 0, newOpStack, 0, fDepth);
254 fOpStack = newOpStack;
255 int [][] newGroupIndexStack = new int[fDepth * 2][];
256 System.arraycopy(fGroupIndexStack, 0, newGroupIndexStack, 0, fDepth);
257 fGroupIndexStack = newGroupIndexStack;
258 int [] newGroupIndexStackLengths = new int[fDepth * 2];
259 System.arraycopy(fGroupIndexStackSizes, 0, newGroupIndexStackLengths, 0, fDepth);
260 fGroupIndexStackSizes = newGroupIndexStackLengths;
261 }
262 fOpStack[fDepth] = -1;
263 fGroupIndexStackSizes[fDepth] = 0;
264 } // initializeContentModelStacks()
265
266 /**
267 * Add XMLContentSpec to the current group.
268 *
269 * @param contentSpec handle to the XMLContentSpec to add to the current group
270 */
271 private void addToCurrentGroup(int contentSpec) {
272 int [] currentGroup = fGroupIndexStack[fDepth];
273 int length = fGroupIndexStackSizes[fDepth]++;
274 if (currentGroup == null) {
275 currentGroup = new int[8];
276 fGroupIndexStack[fDepth] = currentGroup;
277 }
278 else if (length == currentGroup.length) {
279 int [] newGroup = new int[currentGroup.length * 2];
280 System.arraycopy(currentGroup, 0, newGroup, 0, currentGroup.length);
281 currentGroup = newGroup;
282 fGroupIndexStack[fDepth] = currentGroup;
283 }
284 currentGroup[length] = contentSpec;
285 } // addToCurrentGroup(int)
286
287 } // class BalancedDTDGrammar