Java tutorial
/* * 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. */ /* $Id: FONode.java 1310853 2012-04-07 20:23:56Z gadams $ */ package org.apache.fop.fo; // Java import java.util.Iterator; import java.util.ListIterator; import java.util.Map; import java.util.Stack; import org.xml.sax.Attributes; import org.xml.sax.Locator; import org.xml.sax.helpers.LocatorImpl; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.xmlgraphics.util.QName; import org.apache.fop.accessibility.StructureTreeElement; import org.apache.fop.apps.FOPException; import org.apache.fop.apps.FOUserAgent; import org.apache.fop.complexscripts.bidi.DelimitedTextRange; import org.apache.fop.fo.extensions.ExtensionAttachment; import org.apache.fop.fo.extensions.ExtensionElementMapping; import org.apache.fop.fo.extensions.InternalElementMapping; import org.apache.fop.fo.extensions.svg.SVGElementMapping; import org.apache.fop.fo.pagination.Root; import org.apache.fop.util.CharUtilities; import org.apache.fop.util.ContentHandlerFactory; import org.apache.fop.util.text.AdvancedMessageFormat.Function; /** * Base class for nodes in the XML tree */ public abstract class FONode implements Cloneable { /** the XSL-FO namespace URI */ protected static final String FO_URI = FOElementMapping.URI; /** FOP's proprietary extension namespace URI */ protected static final String FOX_URI = ExtensionElementMapping.URI; /** Parent FO node */ protected FONode parent; /** pointer to the sibling nodes */ protected FONode[] siblings; /** * Marks the location of this object from the input FO * <br>Call <code>locator.getSystemId()</code>, * <code>getLineNumber()</code>, * <code>getColumnNumber()</code> for file, line, column * information */ protected Locator locator; /** Logger for fo-tree related messages **/ protected static final Log log = LogFactory.getLog(FONode.class); /** * Base constructor * * @param parent parent of this node */ protected FONode(FONode parent) { this.parent = parent; } /** * Performs a shallow cloning operation, sets the clone's parent, * and optionally cleans the list of child nodes * * @param cloneparent the intended parent of the clone * @param removeChildren if true, clean the list of child nodes * @return the cloned FO node * @throws FOPException if there's a problem while cloning the node */ public FONode clone(FONode cloneparent, boolean removeChildren) throws FOPException { FONode foNode = (FONode) clone(); foNode.parent = cloneparent; foNode.siblings = null; return foNode; } /** {@inheritDoc} */ protected Object clone() { try { return super.clone(); } catch (CloneNotSupportedException e) { throw new AssertionError(); // Can't happen } } /** * Bind the given <code>PropertyList</code> to this node * Does nothing by default. Subclasses should override this method * in case they want to use the properties available on the * <code>PropertyList</code>. * * @param propertyList the <code>PropertyList</code> * @throws FOPException if there was an error when * processing the <code>PropertyList</code> */ public void bind(PropertyList propertyList) throws FOPException { //nop } /** * Set the location information for this element * @param locator the org.xml.sax.Locator object */ public void setLocator(Locator locator) { if (locator != null) { //Create a copy of the locator so the info is preserved when we need to //give pointers during layout. this.locator = new LocatorImpl(locator); } } /** * Returns the <code>Locator</code> containing the location information for this * element, or <code>null</code> if not available * * @return the location information for this element or <code>null</code>, if not available */ public Locator getLocator() { return this.locator; } /** * Recursively goes up the FOTree hierarchy until the <code>fo:root</code> * is found, which returns the parent <code>FOEventHandler</code>. * <br>(see also: {@link org.apache.fop.fo.pagination.Root#getFOEventHandler()}) * * @return the FOEventHandler object that is the parent of the FO Tree */ public FOEventHandler getFOEventHandler() { return parent.getFOEventHandler(); } /** * Returns the context class providing information used during FO tree building. * @return the builder context */ public FOTreeBuilderContext getBuilderContext() { return parent.getBuilderContext(); } /** * Indicates whether this node is a child of an fo:marker. * @return true if this node is a child of an fo:marker */ protected boolean inMarker() { return getBuilderContext().inMarker(); } /** * Returns the user agent that is associated with the * tree's <code>FOEventHandler</code>. * * @return the user agent */ public FOUserAgent getUserAgent() { return getFOEventHandler().getUserAgent(); } /** * Returns the logger for the node. * * @return the logger */ public Log getLogger() { return log; } /** * Initialize the node with its name, location information, and attributes * The attributes must be used immediately as the sax attributes * will be altered for the next element. * * @param elementName element name (e.g., "fo:block") * @param locator Locator object (ignored by default) * @param attlist Collection of attributes passed to us from the parser. * @param pList the property list of the parent node * @throws FOPException for errors or inconsistencies in the attributes */ public void processNode(String elementName, Locator locator, Attributes attlist, PropertyList pList) throws FOPException { if (log.isDebugEnabled()) { log.debug("Unhandled element: " + elementName + (locator != null ? " at " + getLocatorString(locator) : "")); } } /** * Create a property list for this node. Return null if the node does not * need a property list. * * @param pList the closest parent propertylist. * @param foEventHandler The FOEventHandler where the PropertyListMaker * instance can be found. * @return A new property list. * @throws FOPException if there's a problem during processing */ protected PropertyList createPropertyList(PropertyList pList, FOEventHandler foEventHandler) throws FOPException { return null; } /** * Checks to make sure, during SAX processing of input document, that the * incoming node is valid for this (parent) node (e.g., checking to * see that <code>fo:table</code> is not an immediate child of <code>fo:root</code>) * called from {@link FOTreeBuilder#startElement(String, String, String, Attributes)} * before constructing the child {@link FObj}. * * @param loc location in the FO source file * @param namespaceURI namespace of incoming node * @param localName name of the incoming node (without namespace prefix) * @throws ValidationException if incoming node not valid for parent */ protected void validateChildNode(Locator loc, String namespaceURI, String localName) throws ValidationException { //nop } /** * Static version of {@link FONode#validateChildNode(Locator, String, String)} that * can be used by subclasses that need to validate children against a different node * (for example: <code>fo:wrapper</code> needs to check if the incoming node is a * valid child to its parent) * * @param fo the {@link FONode} to validate against * @param loc location in the source file * @param namespaceURI namespace of the incoming node * @param localName name of the incoming node (without namespace prefix) * @throws ValidationException if the incoming node is not a valid child for the given FO */ protected static void validateChildNode(FONode fo, Locator loc, String namespaceURI, String localName) throws ValidationException { fo.validateChildNode(loc, namespaceURI, localName); } /** * Adds characters. Does nothing by default. To be overridden in subclasses * that allow <code>#PCDATA</code> content. * * @param data array of characters containing text to be added * @param start starting array element to add * @param end ending array element to add * @param pList currently applicable PropertyList * @param locator location in the XSL-FO source file. * @throws FOPException if there's a problem during processing * @deprecated Please override {@link #characters(char[], int, int, PropertyList, Locator)} * instead! */ protected void addCharacters(char[] data, int start, int end, PropertyList pList, Locator locator) throws FOPException { // ignore } /** * Adds characters. Does nothing by default. To be overridden in subclasses * that allow <code>#PCDATA</code> content. * * @param data array of characters containing text to be added * @param start starting array element to add * @param length number of elements to add * @param pList currently applicable PropertyList * @param locator location in the XSL-FO source file. * @throws FOPException if there's a problem during processing */ protected void characters(char[] data, int start, int length, PropertyList pList, Locator locator) throws FOPException { addCharacters(data, start, start + length, pList, locator); } /** * Called after processNode() is called. Subclasses can do additional processing. * * @throws FOPException if there's a problem during processing */ protected void startOfNode() throws FOPException { // do nothing by default } /** * Primarily used for making final content model validation checks * and/or informing the {@link FOEventHandler} that the end of this FO * has been reached. * The default implementation simply calls {@link #finalizeNode()}, without * sending any event to the {@link FOEventHandler}. * <br/><i>Note: the recommended way to override this method in subclasses is</i> * <br/><br/><code>super.endOfNode(); // invoke finalizeNode() * <br/>getFOEventHandler().endXXX(); // send endOfNode() notification</code> * * @throws FOPException if there's a problem during processing */ protected void endOfNode() throws FOPException { this.finalizeNode(); } /** * Adds a node as a child of this node. The default implementation of this method * just ignores any child node being added. * * @param child child node to be added to the childNodes of this node * @throws FOPException if there's a problem during processing */ protected void addChildNode(FONode child) throws FOPException { // do nothing by default } /** * Removes a child node. Used by the child nodes to remove themselves, for * example table-body if it has no children. * * @param child child node to be removed */ public void removeChild(FONode child) { //nop } /** * Finalize this node. * This method can be overridden by subclasses to perform finishing * tasks (cleanup, validation checks, ...) without triggering * endXXX() events in the {@link FOEventHandler}. * The method is called by the default {@link #endOfNode()} * implementation. * * @throws FOPException in case there was an error */ public void finalizeNode() throws FOPException { // do nothing by default } /** * Return the parent node of this node * * @return the parent node of this node */ public FONode getParent() { return this.parent; } /** * Return an iterator over all the child nodes of this node. * * @return the iterator over the FO's childnodes */ public FONodeIterator getChildNodes() { return null; } /** * Return an iterator over the object's child nodes starting * at the passed node. * * @param childNode First node in the iterator * @return the iterator, or <code>null</code> if * the given node is not a child of this node. */ public FONodeIterator getChildNodes(FONode childNode) { return null; } /** * Return a {@link CharIterator} over all characters in this node * * @return an iterator for the characters in this node */ public CharIterator charIterator() { return new OneCharIterator(CharUtilities.CODE_EOT); } /** * Helper function to obtain standard usage prefix for FOP related * namespace URIs. * @param namespaceURI URI of node found * (e.g., "http://www.w3.org/1999/XSL/Format") * @return the prefix or null if none */ public static String getNodePrefix(String namespaceURI) { if (namespaceURI.equals(FOElementMapping.URI)) { return "fo"; } else if (namespaceURI.equals(ExtensionElementMapping.URI)) { return "fox"; } else if (namespaceURI.equals(InternalElementMapping.URI)) { return "foi"; } else if (namespaceURI.equals(SVGElementMapping.URI)) { return "svg"; } else { return null; } } /** * Helper function to standardize the names of all namespace URI - local * name pairs in text messages. * For readability, using fo:, fox:, svg:, for those namespaces even * though that prefix may not have been chosen in the document. * @param namespaceURI URI of node found * (e.g., "http://www.w3.org/1999/XSL/Format") * @param localName local name of node, (e.g., "root" for "fo:root") * @return the prefix:localname, if fo/fox/svg, or a longer representation * with the unabbreviated URI otherwise. */ public static String getNodeString(String namespaceURI, String localName) { String prefix = getNodePrefix(namespaceURI); if (prefix != null) { return prefix + ":" + localName; } else { return "(Namespace URI: \"" + namespaceURI + "\", " + "Local Name: \"" + localName + "\")"; } } /** * Returns an instance of the FOValidationEventProducer. * @return an event producer for FO validation */ protected FOValidationEventProducer getFOValidationEventProducer() { return FOValidationEventProducer.Provider.get(getUserAgent().getEventBroadcaster()); } /** * Helper function to standardize "too many" error exceptions * (e.g., two fo:declarations within fo:root) * @param loc org.xml.sax.Locator object of the error (*not* parent node) * @param nsURI namespace URI of incoming invalid node * @param lName local name (i.e., no prefix) of incoming node * @throws ValidationException the validation error provoked by the method call */ protected void tooManyNodesError(Locator loc, String nsURI, String lName) throws ValidationException { tooManyNodesError(loc, new QName(nsURI, lName)); } /** * Helper function to standardize "too many" error exceptions * (e.g., two <code>fo:declarations</code> within <code>fo:root</code>) * * @param loc org.xml.sax.Locator object of the error (*not* parent node) * @param offendingNode the qualified name of the offending node * @throws ValidationException the validation error provoked by the method call */ protected void tooManyNodesError(Locator loc, QName offendingNode) throws ValidationException { getFOValidationEventProducer().tooManyNodes(this, getName(), offendingNode, loc); } /** * Helper function to standardize "too many" error exceptions * (e.g., two fo:declarations within fo:root) * This overloaded method helps make the caller code better self-documenting * @param loc org.xml.sax.Locator object of the error (*not* parent node) * @param offendingNode incoming node that would cause a duplication. * @throws ValidationException the validation error provoked by the method call */ protected void tooManyNodesError(Locator loc, String offendingNode) throws ValidationException { tooManyNodesError(loc, new QName(FO_URI, offendingNode)); } /** * Helper function to standardize "out of order" exceptions * (e.g., <code>fo:layout-master-set</code> appearing after <code>fo:page-sequence</code>) * * @param loc org.xml.sax.Locator object of the error (*not* parent node) * @param tooLateNode string name of node that should be earlier in document * @param tooEarlyNode string name of node that should be later in document * @throws ValidationException the validation error provoked by the method call */ protected void nodesOutOfOrderError(Locator loc, String tooLateNode, String tooEarlyNode) throws ValidationException { nodesOutOfOrderError(loc, tooLateNode, tooEarlyNode, false); } /** * Helper function to standardize "out of order" exceptions * (e.g., fo:layout-master-set appearing after fo:page-sequence) * @param loc org.xml.sax.Locator object of the error (*not* parent node) * @param tooLateNode string name of node that should be earlier in document * @param tooEarlyNode string name of node that should be later in document * @param canRecover indicates whether FOP can recover from this problem and continue working * @throws ValidationException the validation error provoked by the method call */ protected void nodesOutOfOrderError(Locator loc, String tooLateNode, String tooEarlyNode, boolean canRecover) throws ValidationException { getFOValidationEventProducer().nodeOutOfOrder(this, getName(), tooLateNode, tooEarlyNode, canRecover, loc); } /** * Helper function to return "invalid child" exceptions * (e.g., <code>fo:block</code> appearing immediately under <code>fo:root</code>) * * @param loc org.xml.sax.Locator object of the error (*not* parent node) * @param nsURI namespace URI of incoming invalid node * @param lName local name (i.e., no prefix) of incoming node * @throws ValidationException the validation error provoked by the method call */ protected void invalidChildError(Locator loc, String nsURI, String lName) throws ValidationException { invalidChildError(loc, getName(), nsURI, lName, null); } /** * Helper function to return "invalid child" exceptions with more * complex validation rules (i.e., needing more explanation of the problem) * * @param loc org.xml.sax.Locator object of the error (*not* parent node) * @param parentName the name of the parent element * @param nsURI namespace URI of incoming offending node * @param lName local name (i.e., no prefix) of incoming offending node * @param ruleViolated name of the rule violated (used to lookup a resource in a bundle) * @throws ValidationException the validation error provoked by the method call */ protected void invalidChildError(Locator loc, String parentName, String nsURI, String lName, String ruleViolated) throws ValidationException { String prefix = getNodePrefix(nsURI); QName qn; // qualified name of offending node if (prefix != null) { qn = new QName(nsURI, prefix, lName); } else { qn = new QName(nsURI, lName); } getFOValidationEventProducer().invalidChild(this, parentName, qn, ruleViolated, loc); } /** * Helper function to throw an error caused by missing mandatory child elements. * (e.g., <code>fo:layout-master-set</code> not having any <code>fo:page-master</code> * child element. * * @param contentModel The XSL Content Model for the fo: object or a similar description * indicating the necessary child elements. * @throws ValidationException the validation error provoked by the method call */ protected void missingChildElementError(String contentModel) throws ValidationException { getFOValidationEventProducer().missingChildElement(this, getName(), contentModel, false, locator); } /** * Helper function to throw an error caused by missing mandatory child elements. * E.g., fo:layout-master-set not having any page-master child element. * @param contentModel The XSL Content Model for the fo: object or a similar description * indicating the necessary child elements. * @param canRecover indicates whether FOP can recover from this problem and continue working * @throws ValidationException the validation error provoked by the method call */ protected void missingChildElementError(String contentModel, boolean canRecover) throws ValidationException { getFOValidationEventProducer().missingChildElement(this, getName(), contentModel, canRecover, locator); } /** * Helper function to throw an error caused by missing mandatory properties * * @param propertyName the name of the missing property. * @throws ValidationException the validation error provoked by the method call */ protected void missingPropertyError(String propertyName) throws ValidationException { getFOValidationEventProducer().missingProperty(this, getName(), propertyName, locator); } /** * Helper function to return "Error(line#/column#)" string for * above exception messages * * @param loc org.xml.sax.Locator object * @return String opening error text */ protected static String errorText(Locator loc) { return "Error(" + getLocatorString(loc) + "): "; } /** * Helper function to return "Warning(line#/column#)" string for * warning messages * * @param loc org.xml.sax.Locator object * @return String opening warning text */ protected static String warningText(Locator loc) { return "Warning(" + getLocatorString(loc) + "): "; } /** * Helper function to format a Locator instance. * * @param loc org.xml.sax.Locator object * @return String the formatted text */ public static String getLocatorString(Locator loc) { if (loc == null) { return "Unknown location"; } else { return loc.getLineNumber() + "/" + loc.getColumnNumber(); } } /** * Decorates a log or warning message with context information on the given node. * * @param text the original message * @param node the context node * @return the decorated text */ public static String decorateWithContextInfo(String text, FONode node) { if (node != null) { StringBuffer sb = new StringBuffer(text); sb.append(" (").append(node.getContextInfo()).append(")"); return sb.toString(); } else { return text; } } /** * Returns a String containing as much context information as possible about a node. Call * this method only in exceptional conditions because this method may perform quite extensive * information gathering inside the FO tree. * @return a String containing context information */ // [GA] remove deprecation - no alternative specified // @deprecated Not localized! Should rename getContextInfoAlt() to getContextInfo() when done! public String getContextInfo() { StringBuffer sb = new StringBuffer(); if (getLocalName() != null) { sb.append(getName()); sb.append(", "); } if (this.locator != null) { sb.append("location: "); sb.append(getLocatorString(this.locator)); } else { String s = gatherContextInfo(); if (s != null) { sb.append("\""); sb.append(s); sb.append("\""); } else { sb.append("no context info available"); } } if (sb.length() > 80) { sb.setLength(80); } return sb.toString(); } /** * Returns a String containing as some context information about a node. It does not take the * locator into consideration and returns null if no useful context information can be found. * Call this method only in exceptional conditions because this method may perform quite * extensive information gathering inside the FO tree. All text returned by this method that * is not extracted from document content needs to be locale-independent. * @return a String containing context information */ protected String getContextInfoAlt() { String s = gatherContextInfo(); if (s != null) { StringBuffer sb = new StringBuffer(); if (getLocalName() != null) { sb.append(getName()); sb.append(", "); } sb.append("\""); sb.append(s); sb.append("\""); return sb.toString(); } else { return null; } } /** Function for AdvancedMessageFormat to retrieve context info from an FONode. */ public static class GatherContextInfoFunction implements Function { /** {@inheritDoc} */ public Object evaluate(Map params) { Object obj = params.get("source"); if (obj instanceof PropertyList) { PropertyList propList = (PropertyList) obj; obj = propList.getFObj(); } if (obj instanceof FONode) { FONode node = (FONode) obj; return node.getContextInfoAlt(); } return null; } /** {@inheritDoc} */ public Object getName() { return "gatherContextInfo"; } } /** * Gathers context information for the getContextInfo() method. * @return the collected context information or null, if none is available */ protected String gatherContextInfo() { return null; } /** * Returns the root node of this tree * * @return the root node */ public Root getRoot() { return parent.getRoot(); } /** * Returns the fully qualified name of the node * * @return the fully qualified name of this node */ public String getName() { return getName(getNormalNamespacePrefix()); } /** * Returns the fully qualified name of the node * * @param prefix the namespace prefix to build the name with (may be null) * @return the fully qualified name of this node */ public String getName(String prefix) { if (prefix != null) { StringBuffer sb = new StringBuffer(); sb.append(prefix).append(':').append(getLocalName()); return sb.toString(); } else { return getLocalName(); } } /** * Returns the local name (i.e. without namespace prefix) of the node * * @return the local name of this node */ public abstract String getLocalName(); /** * Returns the normally used namespace prefix for this node * * @return the normally used namespace prefix for this kind of node (ex. "fo" for XSL-FO) */ public abstract String getNormalNamespacePrefix(); /** * Returns the namespace URI for this node * * @return the namespace URI for this node */ public String getNamespaceURI() { return null; } /** * Returns the {@link Constants} class integer value of this node * * @return the integer enumeration of this FO (e.g. {@link Constants#FO_ROOT}) * if a formatting object, {@link Constants#FO_UNKNOWN_NODE} otherwise */ public int getNameId() { return Constants.FO_UNKNOWN_NODE; } /** * This method is overridden by extension elements and allows the extension element * to return a pass-through attachment which the parent formatting objects should simply * carry with them but otherwise ignore. This mechanism is used to pass non-standard * information from the FO tree through to the layout engine and the renderers. * * @return the extension attachment if one is created by the extension element, null otherwise. */ public ExtensionAttachment getExtensionAttachment() { return null; } /** * This method is overridden by extension elements and allows the extension element to return * a {@link ContentHandlerFactory}. This factory can create ContentHandler implementations that * handle foreign XML content by either building up a specific DOM, a Java object or something * else. * * @return the <code>ContentHandlerFactory</code> or <code>null</code> if not applicable */ public ContentHandlerFactory getContentHandlerFactory() { return null; } /** * Returns <code>true</code> if <code>fo:marker</code> is allowed as * a child node. * <br>To be overridden <i>only</i> in extension nodes that need it. * * @return true if markers are valid children */ protected boolean canHaveMarkers() { int foId = getNameId(); switch (foId) { case Constants.FO_BASIC_LINK: case Constants.FO_BIDI_OVERRIDE: case Constants.FO_BLOCK: case Constants.FO_BLOCK_CONTAINER: case Constants.FO_FLOW: case Constants.FO_INLINE: case Constants.FO_INLINE_CONTAINER: case Constants.FO_LIST_BLOCK: case Constants.FO_LIST_ITEM: case Constants.FO_LIST_ITEM_BODY: case Constants.FO_LIST_ITEM_LABEL: case Constants.FO_TABLE: case Constants.FO_TABLE_BODY: case Constants.FO_TABLE_HEADER: case Constants.FO_TABLE_FOOTER: case Constants.FO_TABLE_CELL: case Constants.FO_TABLE_AND_CAPTION: case Constants.FO_TABLE_CAPTION: case Constants.FO_WRAPPER: return true; default: return false; } } /** * This method is used when adding child nodes to a FO that already * contains at least one child. In this case, the new child becomes a * sibling to the previous one * * @param precedingSibling the previous child * @param followingSibling the new child */ protected static void attachSiblings(FONode precedingSibling, FONode followingSibling) { if (precedingSibling.siblings == null) { precedingSibling.siblings = new FONode[2]; } if (followingSibling.siblings == null) { followingSibling.siblings = new FONode[2]; } precedingSibling.siblings[1] = followingSibling; followingSibling.siblings[0] = precedingSibling; } /** * Determine if node has a delimited text range boundary. N.B. that we report * this to be true by default, while specific subclasses override this method to report false. * @param boundary one of {EN_BEFORE, EN_AFTER, or EN_BOTH} enumeration constants * @return true if indicated boundary (or boundaries) constitute a delimited text range * boundary. */ public boolean isDelimitedTextRangeBoundary(int boundary) { return true; } /** * Collect the sequence of delimited text ranges, where each new * range is pushed onto RANGES. * @param ranges a stack of delimited text ranges * @return the (possibly) updated stack of delimited text ranges */ public Stack collectDelimitedTextRanges(Stack ranges) { // if boundary before, then push new range if (isRangeBoundaryBefore()) { maybeNewRange(ranges); } // get current range, if one exists DelimitedTextRange currentRange; if (ranges.size() > 0) { currentRange = (DelimitedTextRange) ranges.peek(); } else { currentRange = null; } // proceses this node ranges = collectDelimitedTextRanges(ranges, currentRange); // if boundary after, then push new range if (isRangeBoundaryAfter()) { maybeNewRange(ranges); } return ranges; } /** * Collect the sequence of delimited text ranges, where each new * range is pushed onto RANGES, where default implementation collects ranges * of child nodes. * @param ranges a stack of delimited text ranges * @param currentRange the current range or null (if none) * @return the (possibly) updated stack of delimited text ranges */ protected Stack collectDelimitedTextRanges(Stack ranges, DelimitedTextRange currentRange) { for (Iterator it = getChildNodes(); (it != null) && it.hasNext();) { ranges = ((FONode) it.next()).collectDelimitedTextRanges(ranges); } return ranges; } /** * Determine if this node is a new bidi RANGE block item. * @return true if this node is a new bidi RANGE block item */ public boolean isBidiRangeBlockItem() { return false; } /** * Conditionally add a new delimited text range to RANGES, where new range is * associated with current FONode. A new text range is added unless all of the following are * true: * <ul> * <li>there exists a current range RCUR in RANGES</li> * <li>RCUR is empty</li> * <li>the node of the RCUR is the same node as FN or a descendent node of FN</li> * </ul> * @param ranges stack of delimited text ranges * @return new range (if constructed and pushed onto stack) or current range (if any) or null */ private DelimitedTextRange maybeNewRange(Stack ranges) { DelimitedTextRange rCur = null; // current range (top of range stack) DelimitedTextRange rNew = null; // new range to be pushed onto range stack if (ranges.empty()) { if (isBidiRangeBlockItem()) { rNew = new DelimitedTextRange(this); } } else { rCur = (DelimitedTextRange) ranges.peek(); if (rCur != null) { if (!rCur.isEmpty() || !isSelfOrDescendent(rCur.getNode(), this)) { rNew = new DelimitedTextRange(this); } } } if (rNew != null) { ranges.push(rNew); } else { rNew = rCur; } return rNew; } private boolean isRangeBoundaryBefore() { return isDelimitedTextRangeBoundary(Constants.EN_BEFORE); } private boolean isRangeBoundaryAfter() { return isDelimitedTextRangeBoundary(Constants.EN_AFTER); } /** * Determine if node N2 is the same or a descendent of node N1. */ private static boolean isSelfOrDescendent(FONode n1, FONode n2) { for (FONode n = n2; n != null; n = n.getParent()) { if (n == n1) { return true; } } return false; } /** * Base iterator interface over a FO's children */ public interface FONodeIterator extends ListIterator { /** * Returns the parent node for this iterator's list * of child nodes * * @return the parent node */ FObj parentNode(); /** * Convenience method with return type of FONode * (semantically equivalent to: <code>(FONode) next();</code>) * * @return the next node (if any), as a type FONode */ FONode nextNode(); /** * Convenience method with return type of FONode * (semantically equivalent to: <code>(FONode) previous();</code>) * * @return the previous node (if any), as a type FONode */ FONode previousNode(); /** * Returns the first node in the list, and decreases the index, * so that a subsequent call to <code>hasPrevious()</code> will * return <code>false</code> * * @return the first node in the list */ FONode firstNode(); /** * Returns the last node in the list, and advances the * current position, so that a subsequent call to <code>hasNext()</code> * will return <code>false</code> * * @return the last node in the list */ FONode lastNode(); } /** * Sets the structure tree element. * * @param structureTreeElement set. */ public void setStructureTreeElement(StructureTreeElement structureTreeElement) { throw new UnsupportedOperationException(); } }