content: /*
   * $Header$
   * $Revision$
   * $Date$
   *
   * ====================================================================
   *
   * Copyright 2000-2002 bob mcwhirter & James Strachan.
   * All rights reserved.
   *
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   * 
   *   * Redistributions of source code must retain the above copyright
   *     notice, this list of conditions and the following disclaimer.
   * 
   *   * Redistributions in binary form must reproduce the above copyright
   *     notice, this list of conditions and the following disclaimer in the
   *     documentation and/or other materials provided with the distribution.
   * 
   *   * Neither the name of the Jaxen Project nor the names of its
   *     contributors may be used to endorse or promote products derived 
   *     from this software without specific prior written permission.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
   * IS" AND ANY EXPRESS 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 COPYRIGHT OWNER
   * OR 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 Jaxen Project and was originally
   * created by bob mcwhirter <bob@werken.com> and
   * James Strachan <jstrachan@apache.org>.  For more information on the
   * Jaxen Project, please see <http://www.jaxen.org/>.
   *
   * $Id$
   */
  
  
  
  package org.jaxen.saxpath;
  
  import org.jaxen.JaxenRuntimeException;
  
  
  
  /**
   * 
   * Internal SAXPath class that contains constants representing 
   * XPath operators to avoid a lot of string comparisons. 
   */
  public class Axis
  {
      
      private Axis() {}
      
      // XXX Ultimately these should use the type-safe enum pattern instead
      /** Marker for an invalid axis */
      public final static int INVALID_AXIS       =  0;
  
      /** The <code>child</code> axis */
      public final static int CHILD              =  1;
  
      /** The <code>descendant</code> axis */
      public final static int DESCENDANT         =  2;
  
      /** The <code>parent</code> axis */
      public final static int PARENT             =  3;
  
      /** The <code>ancestor</code> axis */
      public final static int ANCESTOR           =  4;
  
      /** The <code>following-sibling</code> axis */
      public final static int FOLLOWING_SIBLING  =  5;
  
      /** The <code>preceding-sibling</code> axis */
      public final static int PRECEDING_SIBLING  =  6;
  
      /** The <code>following</code> axis */
      public final static int FOLLOWING          =  7;
  
      /** The <code>preceding</code> axis */
      public final static int PRECEDING          =  8;
  
      /** The <code>attribute</code> axis */
      public final static int ATTRIBUTE          =  9;
  
      /** The <code>namespace</code> axis */
      public final static int NAMESPACE          = 10;
  
      /** The <code>self</code> axis */
      public final static int SELF               = 11;
  
      /** The <code>descendant-or-self</code> axis */
      public final static int DESCENDANT_OR_SELF = 12;
  
      /** The <code>ancestor-or-self</code> axis */
      public final static int ANCESTOR_OR_SELF   = 13;
  
      /**
       * <p>
       * Returns the name of the axis.
       * </p>
       * 
       * @param axisNum the axis code
       * @return the name of the axis such as might be used in an XPath expression
       * @throws JaxenRuntimeException if the number does not represent one of the 13
       *     XPath axes
       */
      public static String lookup(int axisNum)
      {
          switch ( axisNum )
          {
              case CHILD:
                  return "child";
  
              case DESCENDANT:
                  return "descendant";
  
              case PARENT:
                  return "parent";
  
              case ANCESTOR:
                  return "ancestor";
  
              case FOLLOWING_SIBLING:
                  return "following-sibling";
  
              case PRECEDING_SIBLING:
                  return "preceding-sibling";
  
              case FOLLOWING:
                  return "following";
  
              case PRECEDING:
                  return "preceding";
  
              case ATTRIBUTE:
                  return "attribute";
  
              case NAMESPACE:
                  return "namespace";
  
              case SELF:
                  return "self";
  
              case DESCENDANT_OR_SELF:
                  return "descendant-or-self";
  
              case ANCESTOR_OR_SELF:
                  return "ancestor-or-self";
          }
  
          throw new JaxenRuntimeException("Illegal Axis Number");
      }
  
      /**
       * <p>
       * Returns the code for an axis given its name.
       * </p>
       * 
       * @param axisName the name of the axis: child, parent, descendant, descendant-or-self, etc.
       * @return the axis code
       */
      public static int lookup(String axisName)
      {
          
          // XXX All these equals calls are a small HotSpot;
          // Need to replace this with a static HashMap
          if ( "child".equals( axisName ) )
          {
              return CHILD;
          }
  
          if ( "descendant".equals( axisName ) )
          {
              return DESCENDANT;
          }
  
          if ( "parent".equals( axisName ) )
          {
              return PARENT;
          }
  
          if ( "ancestor".equals( axisName ) )
          {
              return ANCESTOR;
          }
  
          if ( "following-sibling".equals( axisName ) )
          {
              return FOLLOWING_SIBLING;
          }
  
          if ( "preceding-sibling".equals( axisName ) )
          {
              return PRECEDING_SIBLING;
          }
  
          if ( "following".equals( axisName ) )
          {
              return FOLLOWING;
          }
  
          if ( "preceding".equals( axisName ) )
          {
              return PRECEDING;
          }
  
          if ( "attribute".equals( axisName ) )
          {
              return ATTRIBUTE;
          }
  
          if ( "namespace".equals( axisName ) )
          {
              return NAMESPACE;
          }
  
          if ( "self".equals( axisName ) )
          {
              return SELF;
          }
  
          if ( "descendant-or-self".equals( axisName ) )
          {
              return DESCENDANT_OR_SELF;
          }
  
          if ( "ancestor-or-self".equals( axisName ) )
          {
              return ANCESTOR_OR_SELF;
          }
  
          return INVALID_AXIS;
      }
  }
  