content: /*
   *  This file is part of AndroidIDE.
   *
   *  AndroidIDE is free software: you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  AndroidIDE is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *   along with AndroidIDE.  If not, see <https://www.gnu.org/licenses/>.
   */
  
  /*
   * reserved comment block
   * DO NOT REMOVE OR ALTER!
   */
  /*
   * Copyright 1999-2004 The Apache Software Foundation.
   *
   * 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.
   */
  /*
   * $Id: ExpressionContext.java,v 1.2.4.1 2005/09/10 19:34:03 jeffsuttor Exp $
   */
  package jaxp.sun.org.apache.xalan.internal.extensions;
  
  import jaxp.xml.transform.ErrorListener;
  
  import jaxp.sun.org.apache.xml.internal.utils.QName;
  import jaxp.sun.org.apache.xpath.internal.XPathContext;
  import jaxp.sun.org.apache.xpath.internal.objects.XObject;
  import org.w3c.dom.Node;
  import org.w3c.dom.traversal.NodeIterator;
  
  import jaxp.xml.transform.TransformerException;
  
  /**
   * An object that implements this interface can supply
   * information about the current XPath expression context.
   */
  public interface ExpressionContext
  {
  
    /**
     * Get the current context node.
     * @return The current context node.
     */
    public Node getContextNode();
  
    /**
     * Get the current context node list.
     * @return An iterator for the current context list, as
     * defined in XSLT.
     */
    public NodeIterator getContextNodes();
  
    /**
     * Get the error listener.
     * @return The registered error listener.
     */
    public ErrorListener getErrorListener();
  
    /**
     * Get the value of a node as a number.
     * @param n Node to be converted to a number.  May be null.
     * @return value of n as a number.
     */
    public double toNumber(Node n);
  
    /**
     * Get the value of a node as a string.
     * @param n Node to be converted to a string.  May be null.
     * @return value of n as a string, or an empty string if n is null.
     */
    public String toString(Node n);
  
    /**
     * Get a variable based on it's qualified name.
     *
     * @param qname The qualified name of the variable.
     *
     * @return The evaluated value of the variable.
     *
     * @throws TransformerException
     */
    public XObject getVariableOrParam(QName qname)
              throws TransformerException;
  
    /**
     * Get the XPathContext that owns this ExpressionContext.
     *
     * Note: exslt:function requires the XPathContext to access
     * the variable stack and TransformerImpl.
     *
     * @return The current XPathContext.
     * @throws TransformerException
     */
    public XPathContext getXPathContext()
              throws TransformerException;
  
  }
  