code: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements. See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership. The ASF licenses this file
   * to you 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.
   */
  /*
   * $Id$
   */
  package org.apache.xml.dtm;
  
  /**
   * Specifies values related to XPath Axes.
   * <p>The ancestor, descendant, following, preceding and self axes partition a
   * document (ignoring attribute and namespace nodes): they do not overlap
   * and together they contain all the nodes in the document.</p>
   *
   */
  public final class Axis
  {
  
    /**
     * The ancestor axis contains the ancestors of the context node;
     *  the ancestors of the context node consist of the parent of context
     *  node and the parent's parent and so on; thus, the ancestor axis will
     *  always include the root node, unless the context node is the root node.
     */
    public static final int ANCESTOR = 0;
  
    /**
     * the ancestor-or-self axis contains the context node and the ancestors of
     *  the context node; thus, the ancestor axis will always include the
     *  root node.
     */
    public static final int ANCESTORORSELF = 1;
  
    /**
     * the attribute axis contains the attributes of the context node; the axis
     *  will be empty unless the context node is an element.
     */
    public static final int ATTRIBUTE = 2;
  
    /** The child axis contains the children of the context node. */
    public static final int CHILD = 3;
  
    /**
     * The descendant axis contains the descendants of the context node;
     *  a descendant is a child or a child of a child and so on; thus the
     *  descendant axis never contains attribute or namespace nodes.
     */
    public static final int DESCENDANT = 4;
  
    /**
     * The descendant-or-self axis contains the context node and the
     *  descendants of the context node.
     */
    public static final int DESCENDANTORSELF = 5;
  
    /**
     * the following axis contains all nodes in the same document as the
     *  context node that are after the context node in document order, excluding
     *  any descendants and excluding attribute nodes and namespace nodes.
     */
    public static final int FOLLOWING = 6;
  
    /**
     * The following-sibling axis contains all the following siblings of the
     *  context node; if the context node is an attribute node or namespace node,
     *  the following-sibling axis is empty.
     */
    public static final int FOLLOWINGSIBLING = 7;
  
    /**
     * The namespace axis contains the namespace nodes of the context node; the
     *  axis will be empty unless the context node is an element.
     */
    public static final int NAMESPACEDECLS = 8;
  
    /**
     * The namespace axis contains the namespace nodes of the context node; the
     *  axis will be empty unless the context node is an element.
     */
    public static final int NAMESPACE = 9;
  
    /**
     * The parent axis contains the parent of the context node,
     *  if there is one.
     */
    public static final int PARENT = 10;
  
    /**
     * The preceding axis contains all nodes in the same document as the context
     *  node that are before the context node in document order, excluding any
     *  ancestors and excluding attribute nodes and namespace nodes
     */
    public static final int PRECEDING = 11;
  
    /**
     * The preceding-sibling axis contains all the preceding siblings of the
     *  context node; if the context node is an attribute node or namespace node,
     *  the preceding-sibling axis is empty.
     */
    public static final int PRECEDINGSIBLING = 12;
  
    /** The self axis contains just the context node itself. */
    public static final int SELF = 13;
  
    /**
     * A non-xpath axis, traversing the subtree including the subtree
     *  root, descendants, attributes, and namespace node decls.
     */
    public static final int ALLFROMNODE = 14;
  
    /**
     * A non-xpath axis, traversing the the preceding and the ancestor nodes, 
     * needed for inverseing select patterns to match patterns.
     */
    public static final int PRECEDINGANDANCESTOR = 15;
    
    // ===========================================
    // All axis past this are absolute.
    
    /**
     * A non-xpath axis, returns all nodes in the tree from and including the 
     * root.
     */
    public static final int ALL = 16;
  
    /**
     * A non-xpath axis, returns all nodes that aren't namespaces or attributes, 
     * from and including the root.
     */
    public static final int DESCENDANTSFROMROOT = 17;
  
    /**
     * A non-xpath axis, returns all nodes that aren't namespaces or attributes, 
     * from and including the root.
     */
    public static final int DESCENDANTSORSELFFROMROOT = 18;
  
    /**
     * A non-xpath axis, returns root only.
     */
    public static final int ROOT = 19;
  
    /**
     * A non-xpath axis, for functions.
     */
    public static final int FILTEREDLIST = 20;
  
    /**
     * A table to identify whether an axis is a reverse axis;
     */
    private static final boolean[] isReverse = {
        true,  // ancestor
        true,  // ancestor-or-self
        false, // attribute
        false, // child
        false, // descendant
        false, // descendant-or-self
        false, // following
        false, // following-sibling
        false, // namespace
        false, // namespace-declarations
        false, // parent (one node, has no order)
        true,  // preceding
        true,  // preceding-sibling
        false  // self (one node, has no order)
    };
  
      /** The names of the axes for diagnostic purposes. */
      private static final String[] names =
      {
        "ancestor",  // 0
        "ancestor-or-self",  // 1
        "attribute",  // 2
        "child",  // 3
        "descendant",  // 4
        "descendant-or-self",  // 5
        "following",  // 6
        "following-sibling",  // 7
        "namespace-decls",  // 8
        "namespace",  // 9
        "parent",  // 10
        "preceding",  // 11
        "preceding-sibling",  // 12
        "self",  // 13
        "all-from-node",  // 14
        "preceding-and-ancestor",  // 15
        "all",  // 16
        "descendants-from-root",  // 17
        "descendants-or-self-from-root",  // 18
        "root",  // 19
        "filtered-list"  // 20
      };
  
    public static boolean isReverse(int axis){
        return isReverse[axis];
    }
      
      public static String getNames(int index){
      	return names[index];    
      }
      
      public static int getNamesLength(){
      	return names.length;
      }
  
  }
  