| /* |
| * reserved comment block |
| * DO NOT REMOVE OR ALTER! |
| */ |
| /* |
| * Copyright 1999-2004 The Apache Software Foundation. |
| * |
| * Licensed 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: DTMNodeIterator.java,v 1.2.4.1 2005/09/15 08:15:03 suresh_emailid Exp $ |
| */ |
| package com.sun.org.apache.xml.internal.dtm.ref; |
| |
| import com.sun.org.apache.xml.internal.dtm.DTM; |
| import com.sun.org.apache.xml.internal.dtm.DTMDOMException; |
| import com.sun.org.apache.xml.internal.dtm.DTMIterator; |
| |
| import org.w3c.dom.DOMException; |
| import org.w3c.dom.Node; |
| import org.w3c.dom.traversal.NodeFilter; |
| |
| /** |
| * <code>DTMNodeIterator</code> gives us an implementation of the |
| * DTMNodeIterator which returns DOM nodes. |
| * |
| * Please note that this is not necessarily equivlaent to a DOM |
| * NodeIterator operating over the same document. In particular: |
| * <ul> |
| * |
| * <li>If there are several Text nodes in logical succession (ie, |
| * across CDATASection and EntityReference boundaries), we will return |
| * only the first; the caller is responsible for stepping through |
| * them. |
| * (%REVIEW% Provide a convenience routine here to assist, pending |
| * proposed DOM Level 3 getAdjacentText() operation?) </li> |
| * |
| * <li>Since the whole XPath/XSLT architecture assumes that the source |
| * document is not altered while we're working with it, we do not |
| * promise to implement the DOM NodeIterator's "maintain current |
| * position" response to document mutation. </li> |
| * |
| * <li>Since our design for XPath NodeIterators builds a stateful |
| * filter directly into the traversal object, getNodeFilter() is not |
| * supported.</li> |
| * |
| * </ul> |
| * |
| * <p>State: In progress!!</p> |
| * */ |
| public class DTMNodeIterator implements org.w3c.dom.traversal.NodeIterator |
| { |
| private DTMIterator dtm_iter; |
| private boolean valid=true; |
| |
| //================================================================ |
| // Methods unique to this class |
| |
| /** Public constructor: Wrap a DTMNodeIterator around an existing |
| * and preconfigured DTMIterator |
| * */ |
| public DTMNodeIterator(DTMIterator dtmIterator) |
| { |
| try |
| { |
| dtm_iter=(DTMIterator)dtmIterator.clone(); |
| } |
| catch(CloneNotSupportedException cnse) |
| { |
| throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(cnse); |
| } |
| } |
| |
| /** Access the wrapped DTMIterator. I'm not sure whether anyone will |
| * need this or not, but let's write it and think about it. |
| * */ |
| public DTMIterator getDTMIterator() |
| { |
| return dtm_iter; |
| } |
| |
| |
| //================================================================ |
| // org.w3c.dom.traversal.NodeFilter API follows |
| |
| /** Detaches the NodeIterator from the set which it iterated over, |
| * releasing any computational resources and placing the iterator in |
| * the INVALID state. |
| * */ |
| public void detach() |
| { |
| // Theoretically, we could release dtm_iter at this point. But |
| // some of the operations may still want to consult it even though |
| // navigation is now invalid. |
| valid=false; |
| } |
| |
| /** The value of this flag determines whether the children |
| * of entity reference nodes are visible to the iterator. |
| * |
| * @return false, always (the DTM model flattens entity references) |
| * */ |
| public boolean getExpandEntityReferences() |
| { |
| return false; |
| } |
| |
| /** Return a handle to the filter used to screen nodes. |
| * |
| * This is ill-defined in Xalan's usage of Nodeiterator, where we have |
| * built stateful XPath-based filtering directly into the traversal |
| * object. We could return something which supports the NodeFilter interface |
| * and allows querying whether a given node would be permitted if it appeared |
| * as our next node, but in the current implementation that would be very |
| * complex -- and just isn't all that useful. |
| * |
| * @throws DOMException -- NOT_SUPPORTED_ERROR because I can't think |
| * of anything more useful to do in this case |
| * */ |
| public NodeFilter getFilter() |
| { |
| throw new DTMDOMException(DOMException.NOT_SUPPORTED_ERR); |
| } |
| |
| |
| /** @return The root node of the NodeIterator, as specified |
| * when it was created. |
| * */ |
| public Node getRoot() |
| { |
| int handle=dtm_iter.getRoot(); |
| return dtm_iter.getDTM(handle).getNode(handle); |
| } |
| |
| |
| /** Return a mask describing which node types are presented via the |
| * iterator. |
| **/ |
| public int getWhatToShow() |
| { |
| return dtm_iter.getWhatToShow(); |
| } |
| |
| /** @return the next node in the set and advance the position of the |
| * iterator in the set. |
| * |
| * @throws DOMException - INVALID_STATE_ERR Raised if this method is |
| * called after the detach method was invoked. |
| * */ |
| public Node nextNode() throws DOMException |
| { |
| if(!valid) |
| throw new DTMDOMException(DOMException.INVALID_STATE_ERR); |
| |
| int handle=dtm_iter.nextNode(); |
| if (handle==DTM.NULL) |
| return null; |
| return dtm_iter.getDTM(handle).getNode(handle); |
| } |
| |
| |
| /** @return the next previous in the set and advance the position of the |
| * iterator in the set. |
| * |
| * @throws DOMException - INVALID_STATE_ERR Raised if this method is |
| * called after the detach method was invoked. |
| * */ |
| public Node previousNode() |
| { |
| if(!valid) |
| throw new DTMDOMException(DOMException.INVALID_STATE_ERR); |
| |
| int handle=dtm_iter.previousNode(); |
| if (handle==DTM.NULL) |
| return null; |
| return dtm_iter.getDTM(handle).getNode(handle); |
| } |
| } |