| /* |
| * Copyright 2002-2005 Sascha Weinreuter |
| * |
| * 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.intellij.plugins.xpathView.support.jaxen; |
| |
| import com.intellij.psi.PsiElement; |
| |
| import java.util.Iterator; |
| import java.util.NoSuchElementException; |
| |
| /** |
| * A generic iterator over PSI nodes. |
| * |
| * <p>Concrete subclasses must implement the {@link #getFirstNode} |
| * and {@link #getNextNode} methods for a specific iteration |
| * strategy.</p> |
| */ |
| public abstract class NodeIterator implements Iterator { |
| |
| public NodeIterator(PsiElement contextNode) { |
| node = getFirstNode(contextNode); |
| while (!isXPathNode(node)) |
| node = getNextNode(node); |
| } |
| |
| |
| /** |
| * @see Iterator#hasNext |
| */ |
| public boolean hasNext() { |
| return (node != null); |
| } |
| |
| |
| /** |
| * @see Iterator#next |
| */ |
| public Object next() { |
| if (node == null) |
| throw new NoSuchElementException(); |
| PsiElement ret = node; |
| node = getNextNode(node); |
| while (!isXPathNode(node)) |
| node = getNextNode(node); |
| return ret; |
| } |
| |
| |
| /** |
| * @see Iterator#remove |
| */ |
| public void remove() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| |
| /** |
| * Get the first node for iteration. |
| * |
| * <p>This method must derive an initial node for iteration |
| * from a context node.</p> |
| * |
| * @param contextNode The starting node. |
| * @return The first node in the iteration. |
| * @see #getNextNode |
| */ |
| protected abstract PsiElement getFirstNode(PsiElement contextNode); |
| |
| |
| /** |
| * Get the next node for iteration. |
| * |
| * <p>This method must locate a following node from the |
| * current context node.</p> |
| * |
| * @param contextNode The current node in the iteration. |
| * @return The following node in the iteration, or null |
| * if there is none. |
| * @see #getFirstNode |
| */ |
| protected abstract PsiElement getNextNode(PsiElement contextNode); |
| |
| |
| /** |
| * Test whether a node is usable by XPath. |
| * |
| * @param node The DOM node to test. |
| * @return true if the node is usable, false if it should be |
| * skipped. |
| */ |
| private boolean isXPathNode(PsiElement node) { |
| // null is usable, because it means end |
| if (node == null) |
| return true; |
| |
| // TODO: FIXME |
| return true; |
| } |
| |
| private PsiElement node; |
| } |