/*
* 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: ExsltCommon.java,v 1.2.4.1 2005/09/15 02:45:24 jeffsuttor Exp $
*/
package com.sun.org.apache.xalan.internal.lib;
import com.sun.org.apache.xalan.internal.extensions.ExpressionContext;
import com.sun.org.apache.xml.internal.dtm.DTMIterator;
import com.sun.org.apache.xml.internal.dtm.ref.DTMNodeIterator;
import com.sun.org.apache.xpath.internal.NodeSet;
/**
* This class contains EXSLT common extension functions.
* It is accessed by specifying a namespace URI as follows:
* <pre>
* xmlns:exslt="http://exslt.org/common"
* </pre>
*
* The documentation for each function has been copied from the relevant
* EXSLT Implementer page.
*
* @see <a href="http://www.exslt.org/">EXSLT</a>
* @xsl.usage general
*/
public class ExsltCommon
{
/**
* The exsl:object-type function returns a string giving the type of the object passed
* as the argument. The possible object types are: 'string', 'number', 'boolean',
* 'node-set', 'RTF', or 'external'.
*
* Most XSLT object types can be coerced to each other without error. However, there are
* certain coercions that raise errors, most importantly treating anything other than a
* node set as a node set. Authors of utilities such as named templates or user-defined
* extension functions may wish to give some flexibility in the parameter and argument values
* that are accepted by the utility; the exsl:object-type function enables them to do so.
*
* The Xalan extensions MethodResolver converts 'object-type' to 'objectType'.
*
* @param obj The object to be typed.
* @return objectType 'string', 'number', 'boolean', 'node-set', 'RTF', or 'external'.
*
* @see <a href="http://www.exslt.org/">EXSLT</a>
*/
public static String objectType (Object obj)
{
if (obj instanceof String)
return "string";
else if (obj instanceof Boolean)
return "boolean";
else if (obj instanceof Number)
return "number";
else if (obj instanceof DTMNodeIterator)
{
DTMIterator dtmI = ((DTMNodeIterator)obj).getDTMIterator();
if (dtmI instanceof com.sun.org.apache.xpath.internal.axes.RTFIterator)
return "RTF";
else
return "node-set";
}
else
return "unknown";
}
/**
* The exsl:node-set function converts a result tree fragment (which is what you get
* when you use the content of xsl:variable rather than its select attribute to give
* a variable value) into a node set. This enables you to process the XML that you create
* within a variable, and therefore do multi-step processing.
*
* You can also use this function to turn a string into a text node, which is helpful
* if you want to pass a string to a function that only accepts a node set.
*
* The Xalan extensions MethodResolver converts 'node-set' to 'nodeSet'.
*
* @param myProcessor is passed in by the Xalan extension processor
* @param rtf The result tree fragment to be converted to a node-set.
*
* @return node-set with the contents of the result tree fragment.
*
* Note: Already implemented in the xalan namespace as nodeset.
*
* @see <a href="http://www.exslt.org/">EXSLT</a>
*/
public static NodeSet nodeSet(ExpressionContext myProcessor, Object rtf)
{
return Extensions.nodeset(myProcessor, rtf);
}
}