- /*
- * 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.
- */
- package org.apache.commons.jxpath.ri.model.beans;
-
- import java.util.ArrayList;
- import java.util.List;
-
- import org.apache.commons.jxpath.JXPathException;
- import org.apache.commons.jxpath.ri.model.NodeIterator;
- import org.apache.commons.jxpath.ri.model.NodePointer;
-
- /**
- * Combines node iterators of all elements of a collection into one
- * aggregate node iterator.
- *
- * @author Dmitri Plotnikov
- * @version $Revision: 1.3 $ $Date: 2004/02/29 14:17:41 $
- */
- public abstract class CollectionNodeIterator implements NodeIterator {
- private CollectionPointer pointer;
- private boolean reverse;
- private NodePointer startWith;
- private int position;
- private List collection;
-
- protected CollectionNodeIterator(
- CollectionPointer pointer,
- boolean reverse,
- NodePointer startWith)
- {
- this.pointer = pointer;
- this.reverse = reverse;
- this.startWith = startWith;
- }
-
- /**
- * Implemened by subclasses to produce child/attribute node iterators.
- */
- protected abstract NodeIterator
- getElementNodeIterator(NodePointer elementPointer);
-
- public int getPosition() {
- return position;
- }
-
- public boolean setPosition(int position) {
- if (collection == null) {
- prepare();
- }
-
- if (position < 1 || position > collection.size()) {
- return false;
- }
- this.position = position;
- return true;
- }
-
- public NodePointer getNodePointer() {
- if (position == 0) {
- return null;
- }
- return (NodePointer) collection.get(position - 1);
- }
-
- private void prepare() {
- collection = new ArrayList();
- NodePointer ptr = (NodePointer) pointer.clone();
- int length = ptr.getLength();
- for (int i = 0; i < length; i++) {
- ptr.setIndex(i);
- NodePointer elementPointer = ptr.getValuePointer();
- NodeIterator iter = getElementNodeIterator(elementPointer);
-
- for (int j = 1; iter.setPosition(j); j++) {
- NodePointer childPointer = iter.getNodePointer();
- if (reverse) {
- collection.add(0, childPointer);
- }
- else {
- collection.add(childPointer);
- }
- }
- }
- if (startWith != null) {
- int index = collection.indexOf(startWith);
- if (index == -1) {
- throw new JXPathException(
- "Invalid starting pointer for iterator: " + startWith);
- }
- while (collection.size() > index) {
- if (!reverse) {
- collection.remove(collection.size() - 1);
- }
- else {
- collection.remove(0);
- }
- }
- }
- }
- }