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- /*--
-
- $Id: DescendantIterator.java,v 1.6 2007/11/10 05:28:58 jhunter Exp $
-
- Copyright (C) 2000-2007 Jason Hunter & Brett McLaughlin.
- All rights reserved.
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions
- are met:
-
- 1. Redistributions of source code must retain the above copyright
- notice, this list of conditions, and the following disclaimer.
-
- 2. Redistributions in binary form must reproduce the above copyright
- notice, this list of conditions, and the disclaimer that follows
- these conditions in the documentation and/or other materials
- provided with the distribution.
-
- 3. The name "JDOM" must not be used to endorse or promote products
- derived from this software without prior written permission. For
- written permission, please contact <request_AT_jdom_DOT_org>.
-
- 4. Products derived from this software may not be called "JDOM", nor
- may "JDOM" appear in their name, without prior written permission
- from the JDOM Project Management <request_AT_jdom_DOT_org>.
-
- In addition, we request (but do not require) that you include in the
- end-user documentation provided with the redistribution and/or in the
- software itself an acknowledgement equivalent to the following:
- "This product includes software developed by the
- JDOM Project (http://www.jdom.org/)."
- Alternatively, the acknowledgment may be graphical using the logos
- available at http://www.jdom.org/images/logos.
-
- THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
- WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- DISCLAIMED. IN NO EVENT SHALL THE JDOM AUTHORS OR THE PROJECT
- CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- SUCH DAMAGE.
-
- This software consists of voluntary contributions made by many
- individuals on behalf of the JDOM Project and was originally
- created by Jason Hunter <jhunter_AT_jdom_DOT_org> and
- Brett McLaughlin <brett_AT_jdom_DOT_org>. For more information
- on the JDOM Project, please see <http://www.jdom.org/>.
-
- */
-
- package org.jdom;
-
- import java.util.*;
- import org.jdom.Content;
- import org.jdom.Element;
- import org.jdom.Parent;
-
- /**
- * Traverse all a parent's descendants (all children at any level below
- * the parent).
- *
- * @author Bradley S. Huffman
- * @author Jason Hunter
- * @version $Revision: 1.6 $, $Date: 2007/11/10 05:28:58 $
- */
- class DescendantIterator implements Iterator {
-
- private Iterator iterator;
- private Iterator nextIterator;
- private List stack = new ArrayList();
-
- private static final String CVS_ID =
- "@(#) $RCSfile: DescendantIterator.java,v $ $Revision: 1.6 $ $Date: 2007/11/10 05:28:58 $ $Name: jdom_1_1 $";
-
- /**
- * Iterator for the descendants of the supplied object.
- *
- * @param parent document or element whose descendants will be iterated
- */
- DescendantIterator(Parent parent) {
- if (parent == null) {
- throw new IllegalArgumentException("parent parameter was null");
- }
- this.iterator = parent.getContent().iterator();
- }
-
- /**
- * Returns true> if the iteration has more {@link Content} descendants.
- *
- * @return true is the iterator has more descendants
- */
- public boolean hasNext() {
- if (iterator != null && iterator.hasNext()) return true;
- if (nextIterator != null && nextIterator.hasNext()) return true;
- if (stackHasAnyNext()) return true;
- return false;
- }
-
- /**
- * Returns the next {@link Content} descendant.
- *
- * @return the next descendant
- */
- public Object next() {
- if (!hasNext()) {
- throw new NoSuchElementException();
- }
-
- // If we need to descend, go for it and record where we are.
- // We do the shuffle here on the next next() call so remove() is easy
- // to code up.
- if (nextIterator != null) {
- push(iterator);
- iterator = nextIterator;
- nextIterator = null;
- }
-
- // If this iterator is finished, try moving up the stack
- while (!iterator.hasNext()) {
- if (stack.size() > 0) {
- iterator = pop();
- }
- else {
- throw new NoSuchElementException("Somehow we lost our iterator");
- }
- }
-
- Content child = (Content) iterator.next();
- if (child instanceof Element) {
- nextIterator = ((Element)child).getContent().iterator();
- }
- return child;
- }
-
- /**
- * Detaches the last {@link org.jdom.Content} returned by the last call to
- * next from it's parent. <b>Note</b>: this <b>does not</b> affect
- * iteration and all children, siblings, and any node following the
- * removed node (in document order) will be visited.
- */
- public void remove() {
- iterator.remove();
- }
-
- private Iterator pop() {
- int stackSize = stack.size();
- if (stackSize == 0) {
- throw new NoSuchElementException("empty stack");
- }
- return (Iterator) stack.remove(stackSize - 1);
- }
-
- private void push(Iterator itr) {
- stack.add(itr);
- }
-
- private boolean stackHasAnyNext() {
- int size = stack.size();
- for (int i = 0; i < size; i++) {
- Iterator itr = (Iterator) stack.get(i);
- if (itr.hasNext()) {
- return true;
- }
- }
- return false;
- }
- }
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