/*
 * 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: XRTreeFragSelectWrapper.java 468655 2006-10-28 07:12:06Z minchau $
 */
package org.apache.xpath.objects;

import org.apache.xalan.res.XSLMessages;
import org.apache.xml.dtm.DTMIterator;
import org.apache.xml.utils.XMLString;
import org.apache.xpath.Expression;
import org.apache.xpath.XPathContext;
import org.apache.xpath.res.XPATHErrorResources;

This class makes an select statement act like an result tree fragment.
/**
 * This class makes an select statement act like an result tree fragment.
 */
public class XRTreeFragSelectWrapper extends XRTreeFrag implements Cloneable
{
    static final long serialVersionUID = -6526177905590461251L;
  public XRTreeFragSelectWrapper(Expression expr)
  {
    super(expr);
  }
  
  
This function is used to fixup variables from QNames to stack frame 
indexes at stylesheet build time.
Params:
vars – List of QNames that correspond to variables.  This list 
should be searched backwards for the first qualified name that 
corresponds to the variable reference qname.  The position of the 
QName in the vector from the start of the vector will be its position 
in the stack frame (but variables above the globalsTop value will need 
to be offset to the current stack frame)./**
   * This function is used to fixup variables from QNames to stack frame 
   * indexes at stylesheet build time.
   * @param vars List of QNames that correspond to variables.  This list 
   * should be searched backwards for the first qualified name that 
   * corresponds to the variable reference qname.  The position of the 
   * QName in the vector from the start of the vector will be its position 
   * in the stack frame (but variables above the globalsTop value will need 
   * to be offset to the current stack frame).
   */
  public void fixupVariables(java.util.Vector vars, int globalsSize)
  {
    ((Expression)m_obj).fixupVariables(vars, globalsSize);
  }
  
  
For support of literal objects in xpaths.
Params:
xctxt – The XPath execution context.
Throws:
TransformerException – 
Returns:
the result of executing the select expression/**
   * For support of literal objects in xpaths.
   *
   * @param xctxt The XPath execution context.
   *
   * @return the result of executing the select expression
   *
   * @throws javax.xml.transform.TransformerException
   */
  public XObject execute(XPathContext xctxt)
          throws javax.xml.transform.TransformerException
  {
	 XObject m_selected;
     m_selected = ((Expression)m_obj).execute(xctxt);
     m_selected.allowDetachToRelease(m_allowRelease);
     if (m_selected.getType() == CLASS_STRING)
       return m_selected;
     else
       return new XString(m_selected.str());
  }
    
  
Detaches the DTMIterator from the set which it iterated
over, releasing any computational resources and placing the iterator
in the INVALID state. After detach has been invoked,
calls to nextNode or previousNode will
raise a runtime exception.
In general, detach should only be called once on the object.
/**
   * Detaches the <code>DTMIterator</code> from the set which it iterated
   * over, releasing any computational resources and placing the iterator
   * in the INVALID state. After <code>detach</code> has been invoked,
   * calls to <code>nextNode</code> or <code>previousNode</code> will
   * raise a runtime exception.
   * 
   * In general, detach should only be called once on the object.
   */
  public void detach()
  {
	throw new RuntimeException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_DETACH_NOT_SUPPORTED_XRTREEFRAGSELECTWRAPPER, null)); //"detach() not supported by XRTreeFragSelectWrapper!");
  }
  
  
Cast result object to a number.
Returns:
The result tree fragment as a number or NaN/**
   * Cast result object to a number.
   *
   * @return The result tree fragment as a number or NaN
   */
  public double num()
    throws javax.xml.transform.TransformerException
  {

	throw new RuntimeException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_NUM_NOT_SUPPORTED_XRTREEFRAGSELECTWRAPPER, null)); //"num() not supported by XRTreeFragSelectWrapper!");
  }

  
  
Cast result object to an XMLString.
Returns:
The document fragment node data or the empty string./**
   * Cast result object to an XMLString.
   *
   * @return The document fragment node data or the empty string. 
   */
  public XMLString xstr()
  {
	throw new RuntimeException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_XSTR_NOT_SUPPORTED_XRTREEFRAGSELECTWRAPPER, null)); //"xstr() not supported by XRTreeFragSelectWrapper!");
  }

  
Cast result object to a string.
Returns:
The document fragment node data or the empty string./**
   * Cast result object to a string.
   *
   * @return The document fragment node data or the empty string. 
   */
  public String str()
  {
	throw new RuntimeException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_STR_NOT_SUPPORTED_XRTREEFRAGSELECTWRAPPER, null)); //"str() not supported by XRTreeFragSelectWrapper!");
  }
  
  
Tell what kind of class this is.
Returns:
the string type/**
   * Tell what kind of class this is.
   *
   * @return the string type
   */
  public int getType()
  {
    return CLASS_STRING;
  }

  
Cast result object to a result tree fragment.
Returns:
The document fragment this wraps/**
   * Cast result object to a result tree fragment.
   *
   * @return The document fragment this wraps
   */
  public int rtf()
  {
    throw new RuntimeException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_RTF_NOT_SUPPORTED_XRTREEFRAGSELECTWRAPPER, null)); //"rtf() not supported by XRTreeFragSelectWrapper!");
  }

  
Cast result object to a DTMIterator.
Returns:
The document fragment as a DTMIterator/**
   * Cast result object to a DTMIterator.
   *
   * @return The document fragment as a DTMIterator
   */
  public DTMIterator asNodeIterator()
  {
    throw new RuntimeException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_RTF_NOT_SUPPORTED_XRTREEFRAGSELECTWRAPPER, null)); //"asNodeIterator() not supported by XRTreeFragSelectWrapper!");
  }

}