/*
* Copyright 1999-2005 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: FuncExtFunctionAvailable.java,v 1.13 2005/05/17 21:25:47 jycli Exp $
*/
package org.apache.xpath.functions;
import org.apache.xalan.templates.Constants;
import org.apache.xpath.ExtensionsProvider;
import org.apache.xpath.XPathContext;
import org.apache.xpath.compiler.FunctionTable;
import org.apache.xpath.objects.XBoolean;
import org.apache.xpath.objects.XObject;
/**
* Execute the ExtFunctionAvailable() function.
* @xsl.usage advanced
*/
public class FuncExtFunctionAvailable extends FunctionOneArg
{
static final long serialVersionUID = 5118814314918592241L;
transient private FunctionTable m_functionTable = null;
/**
* 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
{
String prefix;
String namespace;
String methName;
String fullName = m_arg0.execute(xctxt).str();
int indexOfNSSep = fullName.indexOf(':');
if (indexOfNSSep < 0)
{
prefix = "";
namespace = Constants.S_XSLNAMESPACEURL;
methName = fullName;
}
else
{
prefix = fullName.substring(0, indexOfNSSep);
namespace = xctxt.getNamespaceContext().getNamespaceForPrefix(prefix);
if (null == namespace)
return XBoolean.S_FALSE;
methName = fullName.substring(indexOfNSSep + 1);
}
if (namespace.equals(Constants.S_XSLNAMESPACEURL))
{
try
{
if (null == m_functionTable) m_functionTable = new FunctionTable();
return m_functionTable.functionAvailable(methName) ? XBoolean.S_TRUE : XBoolean.S_FALSE;
}
catch (Exception e)
{
return XBoolean.S_FALSE;
}
}
else
{
//dml
ExtensionsProvider extProvider = (ExtensionsProvider)xctxt.getOwnerObject();
return extProvider.functionAvailable(namespace, methName)
? XBoolean.S_TRUE : XBoolean.S_FALSE;
}
}
/**
* The function table is an instance field. In order to access this instance
* field during evaluation, this method is called at compilation time to
* insert function table information for later usage. It should only be used
* during compiling of XPath expressions.
* @param aTable an instance of the function table
*/
public void setFunctionTable(FunctionTable aTable){
m_functionTable = aTable;
}
}