| /******************************************************************************* |
| * Copyright (c) 2005, 2009 Andrea Bittau, University College London, and others |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Andrea Bittau - initial API and implementation from the PsychoPath XPath 2.0 |
| *******************************************************************************/ |
| |
| package org.eclipse.wst.xml.xpath2.processor.internal.ast; |
| |
| import org.eclipse.wst.xml.xpath2.processor.internal.*; |
| |
| /** |
| * Class for Reverse stepping support for Step operations. |
| */ |
| public class ReverseStep extends Step { |
| /** |
| * Set internal value for PARENT. |
| */ |
| public static final int PARENT = 0; |
| /** |
| * Set internal value for ANCESTOR. |
| */ |
| public static final int ANCESTOR = 1; |
| /** |
| * Set internal value for PRECEDING_SIBLING. |
| */ |
| public static final int PRECEDING_SIBLING = 2; |
| /** |
| * Set internal value for PRECEDING. |
| */ |
| public static final int PRECEDING = 3; |
| /** |
| * Set internal value for ANCESTOR_OR_SELF. |
| */ |
| public static final int ANCESTOR_OR_SELF = 4; |
| /** |
| * Set internal value for DOTDOT. |
| */ |
| public static final int DOTDOT = 5; |
| |
| private int _axis; |
| private ReverseAxis _iterator; |
| |
| private void update_iterator() { |
| switch (_axis) { |
| case PARENT: |
| _iterator = new ParentAxis(); |
| break; |
| case ANCESTOR: |
| _iterator = new AncestorAxis(); |
| break; |
| |
| case PRECEDING_SIBLING: |
| _iterator = new PrecedingSiblingAxis(); |
| break; |
| |
| case PRECEDING: |
| _iterator = new PrecedingAxis(); |
| break; |
| |
| case ANCESTOR_OR_SELF: |
| _iterator = new AncestorOrSelfAxis(); |
| break; |
| |
| case DOTDOT: |
| _iterator = null; |
| break; |
| |
| default: |
| assert false; |
| } |
| } |
| |
| /** |
| * Constructor for ReverseStep. |
| * |
| * @param axis |
| * Axis number. |
| * @param node_test |
| * Node test. |
| */ |
| public ReverseStep(int axis, NodeTest node_test) { |
| super(node_test); |
| |
| _axis = axis; |
| update_iterator(); |
| } |
| |
| /** |
| * Support for Visitor interface. |
| * |
| * @return Result of Visitor operation. |
| */ |
| @Override |
| public Object accept(XPathVisitor v) { |
| return v.visit(this); |
| } |
| |
| /** |
| * Support for Axis interface. |
| * |
| * @return Result of Axis operation. |
| */ |
| public int axis() { |
| return _axis; |
| } |
| |
| /** |
| * Support for Iterator interface. |
| * |
| * @return Result of Iterator operation. |
| */ |
| public ReverseAxis iterator() { |
| return _iterator; |
| } |
| } |