/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * 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

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package com.sun.org.apache.xpath.internal.functions;

import com.sun.org.apache.xml.internal.dtm.DTM;

import com.sun.org.apache.xpath.internal.XPathContext;

import com.sun.org.apache.xpath.internal.objects.XObject;

import com.sun.org.apache.xpath.internal.objects.XString;

/**

 * Execute the Namespace() function.

 * @xsl.usage advanced

 */

public class FuncNamespace extends FunctionDef1Arg

{

    static final long serialVersionUID = -4695674566722321237L;

  /**

   * Execute the function.  The function must return

   * a valid object.

   * @param xctxt The current execution context.

   * @return A valid XObject.

   *

   * @throws javax.xml.transform.TransformerException

   */

  public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException

  {

    int context = getArg0AsNode(xctxt);

    String s;

    if(context != DTM.NULL)

    {

      DTM dtm = xctxt.getDTM(context);

      int t = dtm.getNodeType(context);

      if(t == DTM.ELEMENT_NODE)

      {

        s = dtm.getNamespaceURI(context);

      }

      else if(t == DTM.ATTRIBUTE_NODE)

      {

        // This function always returns an empty string for namespace nodes.

        // We check for those here.  Fix inspired by Davanum Srinivas.

        s = dtm.getNodeName(context);

        if(s.startsWith("xmlns:") || s.equals("xmlns"))

          return XString.EMPTYSTRING;

        s = dtm.getNamespaceURI(context);

      }

      else

        return XString.EMPTYSTRING;

    }

    else

      return XString.EMPTYSTRING;

    return ((null == s) ? XString.EMPTYSTRING : new XString(s));

  }

}