bundles/org.eclipse.wst.xsl.core/src_validation/org/eclipse/wst/xsl/core/internal/compiler/xslt10/extensions/ExtensionHandlerExsltFunction.java - sourceediting/webtools.sourceediting.xsl - Git at Google

 /*******************************************************************************
  * Copyright (c) 2007 Standards for Technology in Automotive Retail
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     David Carver - STAR - bug 224197 - initial API and implementation
  *                    based on work from Apache Xalan 2.7.0
  *******************************************************************************/

 /*
  * 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: ExtensionHandlerExsltFunction.java,v 1.3 2008/03/28 02:38:17 dacarver Exp $
  */
 package org.eclipse.wst.xsl.core.internal.compiler.xslt10.extensions;

 import java.io.IOException;
 import java.util.Vector;

 import javax.xml.transform.TransformerException;

 import org.eclipse.wst.xsl.core.compiler.xslt10.res.Messages;
 import org.eclipse.wst.xsl.core.compiler.xslt10.res.XSLTErrorResources;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.Constants;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemExsltFuncResult;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemExsltFunction;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemTemplate;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemTemplateElement;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.Stylesheet;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.StylesheetRoot;
 import org.eclipse.wst.xsl.core.internal.compiler.xslt10.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(
 			org.apache.xml.utils.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.
 	 */
 	@Override
 	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.
 	 */
 	@Override
 	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.
 	 */
 	@Override
 	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
 	 */
 	@Override
 	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
 	 */
 	@Override
 	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.elementAt(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(Messages.createMessage(
 						XSLTErrorResources.ER_FUNCTION_NOT_FOUND,
 						new Object[] { extFunction.getFunctionName() }));
 			}
 		} catch (TransformerException e) {
 			throw e;
 		} catch (Exception e) {
 			throw new TransformerException(e);
 		}
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2007 Standards for Technology in Automotive Retail
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* David Carver - STAR - bug 224197 - initial API and implementation
	* based on work from Apache Xalan 2.7.0
	*******************************************************************************/

	/*
	* 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: ExtensionHandlerExsltFunction.java,v 1.3 2008/03/28 02:38:17 dacarver Exp $
	*/
	package org.eclipse.wst.xsl.core.internal.compiler.xslt10.extensions;

	import java.io.IOException;
	import java.util.Vector;

	import javax.xml.transform.TransformerException;

	import org.eclipse.wst.xsl.core.compiler.xslt10.res.Messages;
	import org.eclipse.wst.xsl.core.compiler.xslt10.res.XSLTErrorResources;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.Constants;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemExsltFuncResult;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemExsltFunction;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemTemplate;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.ElemTemplateElement;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.Stylesheet;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.templates.StylesheetRoot;
	import org.eclipse.wst.xsl.core.internal.compiler.xslt10.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(
	org.apache.xml.utils.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.
	*/
	@Override
	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.
	*/
	@Override
	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.
	*/
	@Override
	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
	*/
	@Override
	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
	*/
	@Override
	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.elementAt(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(Messages.createMessage(
	XSLTErrorResources.ER_FUNCTION_NOT_FOUND,
	new Object[] { extFunction.getFunctionName() }));
	}
	} catch (TransformerException e) {
	throw e;
	} catch (Exception e) {
	throw new TransformerException(e);
	}
	}

	}