/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 1999 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, Lotus
* Development Corporation., http://www.lotus.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.apache.xpath.functions;
import java.util.Vector;
import org.apache.xpath.Expression;
import org.apache.xpath.XPathContext;
import org.apache.xpath.objects.*;
import org.apache.xalan.extensions.ExtensionsTable;
import org.apache.xml.dtm.DTMIterator;
//import org.w3c.dom.Node;
import org.w3c.dom.DocumentFragment;
import org.w3c.dom.traversal.NodeIterator;
/**
* <meta name="usage" content="advanced"/>
* An object of this class represents an extension call expression. When
* the expression executes, it calls ExtensionsTable#extFunction, and then
* converts the result to the appropriate XObject.
*/
public class FuncExtFunction extends Function
{
/**
* The namespace for the extension function, which should not normally
* be null or empty.
* @serial
*/
String m_namespace;
/**
* The local name of the extension.
* @serial
*/
String m_extensionName;
/**
* Unique method key, which is passed to ExtensionsTable#extFunction in
* order to allow caching of the method.
* @serial
*/
Object m_methodKey;
/**
* Array of static expressions which represent the parameters to the
* function.
* @serial
*/
Vector m_argVec = new Vector();
/**
* 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).
* NEEDSDOC @param globalsSize
*/
public void fixupVariables(java.util.Vector vars, int globalsSize)
{
if (null != m_argVec)
{
int nArgs = m_argVec.size();
for (int i = 0; i < nArgs; i++)
{
Expression arg = (Expression) m_argVec.elementAt(i);
arg.fixupVariables(vars, globalsSize);
}
}
}
/**
* Create a new FuncExtFunction based on the qualified name of the extension,
* and a unique method key.
*
* @param namespace The namespace for the extension function, which should
* not normally be null or empty.
* @param extensionName The local name of the extension.
* @param methodKey Unique method key, which is passed to
* ExtensionsTable#extFunction in order to allow caching
* of the method.
*/
public FuncExtFunction(java.lang.String namespace,
java.lang.String extensionName, Object methodKey)
{
m_namespace = namespace;
m_extensionName = extensionName;
m_methodKey = methodKey;
}
/**
* 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
{
XObject result;
Vector argVec = new Vector();
int nArgs = m_argVec.size();
for (int i = 0; i < nArgs; i++)
{
Expression arg = (Expression) m_argVec.elementAt(i);
argVec.addElement(arg.execute(xctxt));
}
ExtensionsTable etable = xctxt.getExtensionsTable();
Object val = etable.extFunction(m_namespace, m_extensionName, argVec,
m_methodKey,
xctxt.getExpressionContext());
if (null != val)
{
if (val instanceof XObject)
{
result = (XObject) val;
}
else if (val instanceof String)
{
result = new XString((String) val);
}
else if (val instanceof Boolean)
{
result = ((Boolean) val).booleanValue()
? XBoolean.S_TRUE : XBoolean.S_FALSE;
}
else if (val instanceof Number)
{
result = new XNumber(((Number) val).doubleValue());
}
else if (val instanceof DocumentFragment)
{
int handle = xctxt.getDTMHandleFromNode((DocumentFragment)val);
result = new XRTreeFrag(handle, xctxt);
}
else if (val instanceof DTMIterator)
{
result = new XNodeSet((DTMIterator) val);
}
else if (val instanceof NodeIterator)
{
result = new XNodeSet(new org.apache.xpath.NodeSetDTM(((NodeIterator)val), xctxt));
}
else if (val instanceof org.w3c.dom.Node)
{
result =
new XNodeSet(xctxt.getDTMHandleFromNode((org.w3c.dom.Node) val),
xctxt.getDTMManager());
}
else
{
result = new XObject(val);
}
}
else
{
result = new XNull();
}
return result;
}
/**
* Set an argument expression for a function. This method is called by the
* XPath compiler.
*
* @param arg non-null expression that represents the argument.
* @param argNum The argument number index.
*
* @throws WrongNumberArgsException If the argNum parameter is beyond what
* is specified for this function.
*/
public void setArg(Expression arg, int argNum)
throws WrongNumberArgsException
{
m_argVec.addElement(arg);
}
/**
* Check that the number of arguments passed to this function is correct.
*
*
* @param argNum The number of arguments that is being passed to the function.
*
* @throws WrongNumberArgsException
*/
public void checkNumberArgs(int argNum) throws WrongNumberArgsException{}
}