org.apache.xerces.impl.dtd.BalancedDTDGrammar Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.xerces.impl.dtd;
import org.apache.xerces.util.SymbolTable;
import org.apache.xerces.xni.Augmentations;
import org.apache.xerces.xni.XMLDTDContentModelHandler;
import org.apache.xerces.xni.XNIException;
/**
* A DTD grammar that produces balanced syntax trees.
*
* @xerces.internal
*
* @author Michael Glavassevich, IBM
* @version $Id: BalancedDTDGrammar.java 965320 2010-07-18 23:25:54Z mrglavas $
*/
final class BalancedDTDGrammar extends DTDGrammar {
//
// Data
//
/** Mixed. */
private boolean fMixed;
/** Stack depth */
private int fDepth = 0;
/** Children content model operation stack. */
private short [] fOpStack = null;
/** Holder for choice/sequence/leaf groups at each depth. */
private int [][] fGroupIndexStack;
/** Sizes of the allocated portions of each int[] in fGroupIndexStack. */
private int [] fGroupIndexStackSizes;
//
// Constructors
//
/** Default constructor. */
public BalancedDTDGrammar(SymbolTable symbolTable, XMLDTDDescription desc) {
super(symbolTable, desc);
} // BalancedDTDGrammar(SymbolTable,XMLDTDDescription)
//
// Public methods
//
/**
* The start of a content model. Depending on the type of the content
* model, specific methods may be called between the call to the
* startContentModel method and the call to the endContentModel method.
*
* @param elementName The name of the element.
* @param augs Additional information that may include infoset
* augmentations.
* @throws XNIException Thrown by handler to signal an error.
*/
public final void startContentModel(String elementName, Augmentations augs)
throws XNIException {
fDepth = 0;
initializeContentModelStacks();
super.startContentModel(elementName, augs);
} // startContentModel(String)
/**
* A start of either a mixed or children content model. A mixed
* content model will immediately be followed by a call to the
* pcdata() method. A children content model will
* contain additional groups and/or elements.
*
* @param augs Additional information that may include infoset
* augmentations.
* @throws XNIException Thrown by handler to signal an error.
*
* @see #any
* @see #empty
*/
public final void startGroup(Augmentations augs) throws XNIException {
++fDepth;
initializeContentModelStacks();
fMixed = false;
} // startGroup()
/**
* The appearance of "#PCDATA" within a group signifying a
* mixed content model. This method will be the first called
* following the content model's startGroup().
*
*@param augs Additional information that may include infoset
* augmentations.
*
* @throws XNIException Thrown by handler to signal an error.
*
* @see #startGroup
*/
public final void pcdata(Augmentations augs) throws XNIException {
fMixed = true;
} // pcdata()
/**
* A referenced element in a mixed or children content model.
*
* @param elementName The name of the referenced element.
* @param augs Additional information that may include infoset
* augmentations.
*
* @throws XNIException Thrown by handler to signal an error.
*/
public final void element(String elementName, Augmentations augs) throws XNIException {
addToCurrentGroup(addUniqueLeafNode(elementName));
} // element(String)
/**
* The separator between choices or sequences of a mixed or children
* content model.
*
* @param separator The type of children separator.
* @param augs Additional information that may include infoset
* augmentations.
* @throws XNIException Thrown by handler to signal an error.
*
* @see org.apache.xerces.xni.XMLDTDContentModelHandler#SEPARATOR_CHOICE
* @see org.apache.xerces.xni.XMLDTDContentModelHandler#SEPARATOR_SEQUENCE
*/
public final void separator(short separator, Augmentations augs) throws XNIException {
if (separator == XMLDTDContentModelHandler.SEPARATOR_CHOICE) {
fOpStack[fDepth] = XMLContentSpec.CONTENTSPECNODE_CHOICE;
}
else if (separator == XMLDTDContentModelHandler.SEPARATOR_SEQUENCE) {
fOpStack[fDepth] = XMLContentSpec.CONTENTSPECNODE_SEQ;
}
} // separator(short)
/**
* The occurrence count for a child in a children content model or
* for the mixed content model group.
*
* @param occurrence The occurrence count for the last element
* or group.
* @param augs Additional information that may include infoset
* augmentations.
* @throws XNIException Thrown by handler to signal an error.
*
* @see org.apache.xerces.xni.XMLDTDContentModelHandler#OCCURS_ZERO_OR_ONE
* @see org.apache.xerces.xni.XMLDTDContentModelHandler#OCCURS_ZERO_OR_MORE
* @see org.apache.xerces.xni.XMLDTDContentModelHandler#OCCURS_ONE_OR_MORE
*/
public final void occurrence(short occurrence, Augmentations augs) throws XNIException {
if (!fMixed) {
int currentIndex = fGroupIndexStackSizes[fDepth] - 1;
if (occurrence == XMLDTDContentModelHandler.OCCURS_ZERO_OR_ONE) {
fGroupIndexStack[fDepth][currentIndex] = addContentSpecNode(XMLContentSpec.CONTENTSPECNODE_ZERO_OR_ONE, fGroupIndexStack[fDepth][currentIndex], -1);
}
else if ( occurrence == XMLDTDContentModelHandler.OCCURS_ZERO_OR_MORE) {
fGroupIndexStack[fDepth][currentIndex] = addContentSpecNode(XMLContentSpec.CONTENTSPECNODE_ZERO_OR_MORE, fGroupIndexStack[fDepth][currentIndex], -1);
}
else if ( occurrence == XMLDTDContentModelHandler.OCCURS_ONE_OR_MORE) {
fGroupIndexStack[fDepth][currentIndex] = addContentSpecNode(XMLContentSpec.CONTENTSPECNODE_ONE_OR_MORE, fGroupIndexStack[fDepth][currentIndex], -1);
}
}
} // occurrence(short)
/**
* The end of a group for mixed or children content models.
*
* @param augs Additional information that may include infoset
* augmentations.
* @throws XNIException Thrown by handler to signal an error.
*/
public final void endGroup(Augmentations augs) throws XNIException {
final int length = fGroupIndexStackSizes[fDepth];
final int group = length > 0 ? addContentSpecNodes(0, length - 1) : addUniqueLeafNode(null);
--fDepth;
addToCurrentGroup(group);
} // endGroup()
/**
* The end of the DTD.
*
* @param augs Additional information that may include infoset
* augmentations.
* @throws XNIException Thrown by handler to signal an error.
*/
public final void endDTD(Augmentations augs) throws XNIException {
super.endDTD(augs);
fOpStack = null;
fGroupIndexStack = null;
fGroupIndexStackSizes = null;
} // endDTD()
//
// Protected methods
//
/**
* Adds the content spec to the given element declaration.
*/
protected final void addContentSpecToElement(XMLElementDecl elementDecl) {
int contentSpec = fGroupIndexStackSizes[0] > 0 ? fGroupIndexStack[0][0] : -1;
setContentSpecIndex(fCurrentElementIndex, contentSpec);
}
//
// Private methods
//
/**
* Creates a subtree from the leaf nodes at the current depth.
*/
private int addContentSpecNodes(int begin, int end) {
if (begin == end) {
return fGroupIndexStack[fDepth][begin];
}
final int middle = (begin + end) >>> 1;
return addContentSpecNode(fOpStack[fDepth],
addContentSpecNodes(begin, middle),
addContentSpecNodes(middle + 1, end));
} // addContentSpecNodes(int,int)
/**
* Initialize the stacks which temporarily hold content models.
*/
private void initializeContentModelStacks() {
if (fOpStack == null) {
fOpStack = new short[8];
fGroupIndexStack = new int [8][];
fGroupIndexStackSizes = new int [8];
}
else if (fDepth == fOpStack.length) {
short [] newOpStack = new short[fDepth * 2];
System.arraycopy(fOpStack, 0, newOpStack, 0, fDepth);
fOpStack = newOpStack;
int [][] newGroupIndexStack = new int[fDepth * 2][];
System.arraycopy(fGroupIndexStack, 0, newGroupIndexStack, 0, fDepth);
fGroupIndexStack = newGroupIndexStack;
int [] newGroupIndexStackLengths = new int[fDepth * 2];
System.arraycopy(fGroupIndexStackSizes, 0, newGroupIndexStackLengths, 0, fDepth);
fGroupIndexStackSizes = newGroupIndexStackLengths;
}
fOpStack[fDepth] = -1;
fGroupIndexStackSizes[fDepth] = 0;
} // initializeContentModelStacks()
/**
* Add XMLContentSpec to the current group.
*
* @param contentSpec handle to the XMLContentSpec to add to the current group
*/
private void addToCurrentGroup(int contentSpec) {
int [] currentGroup = fGroupIndexStack[fDepth];
int length = fGroupIndexStackSizes[fDepth]++;
if (currentGroup == null) {
currentGroup = new int[8];
fGroupIndexStack[fDepth] = currentGroup;
}
else if (length == currentGroup.length) {
int [] newGroup = new int[currentGroup.length * 2];
System.arraycopy(currentGroup, 0, newGroup, 0, currentGroup.length);
currentGroup = newGroup;
fGroupIndexStack[fDepth] = currentGroup;
}
currentGroup[length] = contentSpec;
} // addToCurrentGroup(int)
} // class BalancedDTDGrammar