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Tool to convert CSV and XLS to XML, to transform XML and to convert XML to CSV, HTML, other text files, PDF etc., useful as command line tool and integrated in other projects.
/*
* 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: ExtensionHandlerExsltFunction.java 469672 2006-10-31 21:56:19Z minchau $
*/
package org.apache.xalan.extensions;
import java.io.IOException;
import java.util.Vector;
import javax.xml.transform.TransformerException;
import org.apache.xalan.res.XSLMessages;
import org.apache.xalan.res.XSLTErrorResources;
import org.apache.xalan.templates.Constants;
import org.apache.xalan.templates.ElemExsltFuncResult;
import org.apache.xalan.templates.ElemExsltFunction;
import org.apache.xalan.templates.ElemTemplate;
import org.apache.xalan.templates.ElemTemplateElement;
import org.apache.xalan.templates.Stylesheet;
import org.apache.xalan.templates.StylesheetRoot;
import org.apache.xalan.transformer.TransformerImpl;
import org.apache.xml.utils.QName;
import org.apache.xpath.ExpressionNode;
import org.apache.xpath.XPathContext;
import org.apache.xpath.functions.FuncExtFunction;
import org.apache.xpath.objects.XObject;
import org.apache.xpath.objects.XString;
/**
* Execute EXSLT functions, determine the availability of EXSLT functions, and the
* availability of an EXSLT result element.
*/
public class ExtensionHandlerExsltFunction extends ExtensionHandler
{
private String m_namespace;
private StylesheetRoot m_stylesheet;
private static final QName RESULTQNAME =
new QName(Constants.S_EXSLT_FUNCTIONS_URL,
Constants.EXSLT_ELEMNAME_FUNCRESULT_STRING);
/**
* Constructor called from ElemExsltFunction runtimeInit().
*/
public ExtensionHandlerExsltFunction(String ns, StylesheetRoot stylesheet)
{
super(ns, "xml"); // required by ExtensionHandler interface.
m_namespace = ns;
m_stylesheet = stylesheet;
}
/**
* Required by ExtensionHandler (an abstract method). No-op.
*/
public void processElement(
String localPart, ElemTemplateElement element, TransformerImpl transformer,
Stylesheet stylesheetTree, Object methodKey) throws TransformerException, IOException
{}
/**
* Get the ElemExsltFunction element associated with the
* function.
*
* @param funcName Local name of the function.
* @return the ElemExsltFunction element associated with
* the function, null if none exists.
*/
public ElemExsltFunction getFunction(String funcName)
{
QName qname = new QName(m_namespace, funcName);
ElemTemplate templ = m_stylesheet.getTemplateComposed(qname);
if (templ != null && templ instanceof ElemExsltFunction)
return (ElemExsltFunction) templ;
else
return null;
}
/**
* Does the EXSLT function exist?
*
* @param funcName Local name of the function.
* @return true if the function exists.
*/
public boolean isFunctionAvailable(String funcName)
{
return getFunction(funcName)!= null;
}
/** If an element-available() call applies to an EXSLT result element within
* an EXSLT function element, return true.
*
* Note: The EXSLT function element is a template-level element, and
* element-available() returns false for it.
*
* @param elemName name of the element.
* @return true if the function is available.
*/
public boolean isElementAvailable(String elemName)
{
if (!(new QName(m_namespace, elemName).equals(RESULTQNAME)))
{
return false;
}
else
{
ElemTemplateElement elem = m_stylesheet.getFirstChildElem();
while (elem != null && elem != m_stylesheet)
{
if (elem instanceof ElemExsltFuncResult && ancestorIsFunction(elem))
return true;
ElemTemplateElement nextElem = elem.getFirstChildElem();
if (nextElem == null)
nextElem = elem.getNextSiblingElem();
if (nextElem == null)
nextElem = elem.getParentElem();
elem = nextElem;
}
}
return false;
}
/**
* Determine whether the func:result element is within a func:function element.
* If not, it is illegal.
*/
private boolean ancestorIsFunction(ElemTemplateElement child)
{
while (child.getParentElem() != null
&& !(child.getParentElem() instanceof StylesheetRoot))
{
if (child.getParentElem() instanceof ElemExsltFunction)
return true;
child = child.getParentElem();
}
return false;
}
/**
* Execute the EXSLT function and return the result value.
*
* @param funcName Name of the EXSLT function.
* @param args The arguments of the function call.
* @param methodKey Not used.
* @param exprContext Used to get the XPathContext.
* @return the return value of the function evaluation.
* @throws TransformerException
*/
public Object callFunction(
String funcName, Vector args, Object methodKey,
ExpressionContext exprContext) throws TransformerException
{
throw new TransformerException("This method should not be called.");
}
/**
* Execute the EXSLT function and return the result value.
*
* @param extFunction The XPath extension function
* @param args The arguments of the function call.
* @param exprContext The context in which this expression is being executed.
* @return the return value of the function evaluation.
* @throws TransformerException
*/
public Object callFunction(FuncExtFunction extFunction,
Vector args,
ExpressionContext exprContext)
throws TransformerException
{
// Find the template which invokes this EXSLT function.
ExpressionNode parent = extFunction.exprGetParent();
while (parent != null && !(parent instanceof ElemTemplate))
{
parent = parent.exprGetParent();
}
ElemTemplate callerTemplate = (parent != null) ? (ElemTemplate)parent: null;
XObject[] methodArgs;
methodArgs = new XObject[args.size()];
try
{
for (int i = 0; i < methodArgs.length; i++)
{
methodArgs[i] = XObject.create(args.get(i));
}
ElemExsltFunction elemFunc = getFunction(extFunction.getFunctionName());
if (null != elemFunc) {
XPathContext context = exprContext.getXPathContext();
TransformerImpl transformer = (TransformerImpl)context.getOwnerObject();
transformer.pushCurrentFuncResult(null);
elemFunc.execute(transformer, methodArgs);
XObject val = (XObject)transformer.popCurrentFuncResult();
return (val == null) ? new XString("") // value if no result element.
: val;
}
else {
throw new TransformerException(XSLMessages.createMessage(XSLTErrorResources.ER_FUNCTION_NOT_FOUND, new Object[] {extFunction.getFunctionName()}));
}
}
catch (TransformerException e)
{
throw e;
}
catch (Exception e)
{
throw new TransformerException(e);
}
}
}