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.xalan.lib;
  
  import javax.xml.transform.SourceLocator;
  
  import org.apache.xalan.extensions.ExpressionContext;
  import org.apache.xml.dtm.ref.DTMNodeProxy;
  
  import org.w3c.dom.Node;
  import org.w3c.dom.NodeList;
  
  /**
   * <code>NodeInfo</code> defines a set of XSLT extension functions to be
   * used from stylesheets.
   *
   * @author <a href="mailto:ovidiu@cup.hp.com">Ovidiu Predescu</a>
   * @since May 24, 2001
   */
  public class NodeInfo
  {
    /**
     * <code>systemId</code> returns the system id of the current
     * context node.
     *
     * @param context an <code>ExpressionContext</code> value
     * @return a <code>String</code> value
     */
    public static String systemId(ExpressionContext context)
    {
      Node contextNode = context.getContextNode();
      int nodeHandler = ((DTMNodeProxy)contextNode).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)contextNode).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getSystemId();
      else
        return null;
    }
  
    /**
     * <code>systemId</code> returns the system id of the node passed as
     * argument. If a node set is passed as argument, the system id of
     * the first node in the set is returned.
     *
     * @param nodeList a <code>NodeList</code> value
     * @return a <code>String</code> value
     */
    public static String systemId(NodeList nodeList)
    {
      if (nodeList == null || nodeList.getLength() == 0)
        return null;
      
      Node node = nodeList.item(0);
      int nodeHandler = ((DTMNodeProxy)node).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)node).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getSystemId();
      else
        return null;
    }
  
    /**
     * <code>publicId</code> returns the public identifier of the current
     * context node.
     * 
     * Xalan does not currently record this value, and will return null.
     *
     * @param context an <code>ExpressionContext</code> value
     * @return a <code>String</code> value
     */
    public static String publicId(ExpressionContext context)
    {
      Node contextNode = context.getContextNode();
      int nodeHandler = ((DTMNodeProxy)contextNode).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)contextNode).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getPublicId();
      else
        return null;
    }
  
    /**
     * <code>publicId</code> returns the public identifier of the node passed as
     * argument. If a node set is passed as argument, the public identifier of
     * the first node in the set is returned.
     * 
     * Xalan does not currently record this value, and will return null.
     *
     * @param nodeList a <code>NodeList</code> value
     * @return a <code>String</code> value
     */
    public static String publicId(NodeList nodeList)
    {
      if (nodeList == null || nodeList.getLength() == 0)
        return null;
      
      Node node = nodeList.item(0);
      int nodeHandler = ((DTMNodeProxy)node).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)node).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getPublicId();
      else
        return null;
    }
  
    /**
     * <code>lineNumber</code> returns the line number of the current
     * context node.
     * 
     * NOTE: Xalan does not normally record location information for each node. 
     * To obtain it, you must set the custom TrAX attribute 
     * "http://xml.apache.org/xalan/features/source_location"
     * true in the TransformerFactory before generating the Transformer and executing
     * the stylesheet. Storage cost per node will be noticably increased in this mode.
     *
     * @param context an <code>ExpressionContext</code> value
     * @return an <code>int</code> value. This may be -1 to indicate that the
     * line number is not known.
     */
    public static int lineNumber(ExpressionContext context)
    {
      Node contextNode = context.getContextNode();
      int nodeHandler = ((DTMNodeProxy)contextNode).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)contextNode).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getLineNumber();
      else
        return -1;
    }
  
    /**
     * <code>lineNumber</code> returns the line number of the node
     * passed as argument. If a node set is passed as argument, the line
     * number of the first node in the set is returned.
     *
     * NOTE: Xalan does not normally record location information for each node. 
     * To obtain it, you must set the custom TrAX attribute 
     * "http://xml.apache.org/xalan/features/source_location"
     * true in the TransformerFactory before generating the Transformer and executing
     * the stylesheet. Storage cost per node will be noticably increased in this mode.
     *
     * @param nodeList a <code>NodeList</code> value
     * @return an <code>int</code> value. This may be -1 to indicate that the
     * line number is not known.
     */
    public static int lineNumber(NodeList nodeList)
    {
      if (nodeList == null || nodeList.getLength() == 0)
        return -1;
      
      Node node = nodeList.item(0);
      int nodeHandler = ((DTMNodeProxy)node).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)node).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getLineNumber();
      else
        return -1;
    }
  
    /**
     * <code>columnNumber</code> returns the column number of the
     * current context node.
     *
     * NOTE: Xalan does not normally record location information for each node. 
     * To obtain it, you must set the custom TrAX attribute 
     * "http://xml.apache.org/xalan/features/source_location"
     * true in the TransformerFactory before generating the Transformer and executing
     * the stylesheet. Storage cost per node will be noticably increased in this mode.
     *
     * @param context an <code>ExpressionContext</code> value
     * @return an <code>int</code> value. This may be -1 to indicate that the
     * column number is not known.
     */
    public static int columnNumber(ExpressionContext context)
    {
      Node contextNode = context.getContextNode();
      int nodeHandler = ((DTMNodeProxy)contextNode).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)contextNode).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getColumnNumber();
      else
        return -1;
    }
  
    /**
     * <code>columnNumber</code> returns the column number of the node
     * passed as argument. If a node set is passed as argument, the line
     * number of the first node in the set is returned.
     *
     * NOTE: Xalan does not normally record location information for each node. 
     * To obtain it, you must set the custom TrAX attribute 
     * "http://xml.apache.org/xalan/features/source_location"
     * true in the TransformerFactory before generating the Transformer and executing
     * the stylesheet. Storage cost per node will be noticably increased in this mode.
     *
     * @param nodeList a <code>NodeList</code> value
     * @return an <code>int</code> value. This may be -1 to indicate that the
     * column number is not known.
     */
    public static int columnNumber(NodeList nodeList)
    {
      if (nodeList == null || nodeList.getLength() == 0)
        return -1;
      
      Node node = nodeList.item(0);
      int nodeHandler = ((DTMNodeProxy)node).getDTMNodeNumber();
      SourceLocator locator = ((DTMNodeProxy)node).getDTM()
        .getSourceLocatorFor(nodeHandler);
  
      if (locator != null)
        return locator.getColumnNumber();
      else
        return -1;
    }
  }
  