/*
* 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: ExtensionHandlerGeneral.java,v 1.26 2005/01/23 00:10:05 mcnamara Exp $
*/
package org.apache.xalan.extensions;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Method;
import java.net.URL;
import java.net.URLConnection;
import java.util.Hashtable;
import java.util.Vector;
import javax.xml.transform.TransformerException;
import org.apache.xml.res.XMLErrorResources;
import org.apache.xml.res.XMLMessages;
import org.apache.xalan.res.XSLMessages;
import org.apache.xalan.res.XSLTErrorResources;
import org.apache.xalan.templates.ElemTemplateElement;
import org.apache.xalan.templates.Stylesheet;
import org.apache.xalan.transformer.TransformerImpl;
import org.apache.xml.dtm.DTMIterator;
import org.apache.xml.dtm.ref.DTMNodeList;
import org.apache.xml.utils.StringVector;
import org.apache.xml.utils.SystemIDResolver;
import org.apache.xpath.XPathProcessorException;
import org.apache.xpath.functions.FuncExtFunction;
import org.apache.xpath.objects.XObject;
/**
* Class handling an extension namespace for XPath. Provides functions
* to test a function's existence and call a function
*
* @author Sanjiva Weerawarana (sanjiva@watson.ibm.com)
* @xsl.usage internal
*/
public class ExtensionHandlerGeneral extends ExtensionHandler
{
/** script source to run (if any) */
private String m_scriptSrc;
/** URL of source of script (if any) */
private String m_scriptSrcURL;
/** functions of namespace */
private Hashtable m_functions = new Hashtable();
/** elements of namespace */
private Hashtable m_elements = new Hashtable();
// BSF objects used to invoke BSF by reflection. Do not import the BSF classes
// since we don't want a compile dependency on BSF.
/** BSF manager used to run scripts */
private Object m_engine;
/** Engine call to invoke scripts */
private Method m_engineCall = null;
// static fields
/** BSFManager package name */
private static String BSF_MANAGER ;
/** Default BSFManager name */
private static final String DEFAULT_BSF_MANAGER = "org.apache.bsf.BSFManager";
/** Property name to load the BSFManager class */
private static final String propName = "org.apache.xalan.extensions.bsf.BSFManager";
/** Integer Zero */
private static final Integer ZEROINT = new Integer(0);
static{
BSF_MANAGER = ObjectFactory.lookUpFactoryClassName(propName, null, null);
if (BSF_MANAGER == null){
BSF_MANAGER = DEFAULT_BSF_MANAGER;
}
}
/**
* Construct a new extension namespace handler given all the information
* needed.
*
* @param namespaceUri the extension namespace URI that I'm implementing
* @param elemNames Vector of element names
* @param funcNames string containing list of functions of extension NS
* @param scriptLang Scripting language of implementation
* @param scriptSrcURL URL of source script
* @param scriptSrc the actual script code (if any)
* @param systemId
*
* @throws javax.xml.transform.TransformerException
*/
public ExtensionHandlerGeneral(
String namespaceUri, StringVector elemNames, StringVector funcNames, String scriptLang, String scriptSrcURL, String scriptSrc, String systemId)
throws TransformerException
{
super(namespaceUri, scriptLang);
if (elemNames != null)
{
Object junk = new Object();
int n = elemNames.size();
for (int i = 0; i < n; i++)
{
String tok = elemNames.elementAt(i);
m_elements.put(tok, junk); // just stick it in there basically
}
}
if (funcNames != null)
{
Object junk = new Object();
int n = funcNames.size();
for (int i = 0; i < n; i++)
{
String tok = funcNames.elementAt(i);
m_functions.put(tok, junk); // just stick it in there basically
}
}
m_scriptSrcURL = scriptSrcURL;
m_scriptSrc = scriptSrc;
if (m_scriptSrcURL != null)
{
URL url = null;
try{
url = new URL(m_scriptSrcURL);
}
catch (java.net.MalformedURLException mue)
{
int indexOfColon = m_scriptSrcURL.indexOf(':');
int indexOfSlash = m_scriptSrcURL.indexOf('/');
if ((indexOfColon != -1) && (indexOfSlash != -1)
&& (indexOfColon < indexOfSlash))
{
// The url is absolute.
url = null;
throw new TransformerException(XSLMessages.createMessage(XSLTErrorResources.ER_COULD_NOT_FIND_EXTERN_SCRIPT, new Object[]{m_scriptSrcURL}), mue); //"src attribute not yet supported for "
//+ scriptLang);
}
else
{
try{
url = new URL(new URL(SystemIDResolver.getAbsoluteURI(systemId)), m_scriptSrcURL);
}
catch (java.net.MalformedURLException mue2)
{
throw new TransformerException(XSLMessages.createMessage(XSLTErrorResources.ER_COULD_NOT_FIND_EXTERN_SCRIPT, new Object[]{m_scriptSrcURL}), mue2); //"src attribute not yet supported for "
//+ scriptLang);
}
}
}
if (url != null)
{
try
{
URLConnection uc = url.openConnection();
InputStream is = uc.getInputStream();
byte []bArray = new byte[uc.getContentLength()];
is.read(bArray);
m_scriptSrc = new String(bArray);
}
catch (IOException ioe)
{
throw new TransformerException(XSLMessages.createMessage(XSLTErrorResources.ER_COULD_NOT_FIND_EXTERN_SCRIPT, new Object[]{m_scriptSrcURL}), ioe); //"src attribute not yet supported for "
//+ scriptLang);
}
}
}
Object manager = null;
try
{
manager = ObjectFactory.newInstance(
BSF_MANAGER, ObjectFactory.findClassLoader(), true);
}
catch (ObjectFactory.ConfigurationError e)
{
e.printStackTrace();
}
if (manager == null)
{
throw new TransformerException(XSLMessages.createMessage(XSLTErrorResources.ER_CANNOT_INIT_BSFMGR, null)); //"Could not initialize BSF manager");
}
try
{
Method loadScriptingEngine = manager.getClass()
.getMethod("loadScriptingEngine", new Class[]{ String.class });
m_engine = loadScriptingEngine.invoke(manager,
new Object[]{ scriptLang });
Method engineExec = m_engine.getClass().getMethod("exec",
new Class[]{ String.class, Integer.TYPE, Integer.TYPE, Object.class });
// "Compile" the program
engineExec.invoke(m_engine,
new Object[]{ "XalanScript", ZEROINT, ZEROINT, m_scriptSrc });
}
catch (Exception e)
{
e.printStackTrace();
throw new TransformerException(XSLMessages.createMessage(XSLTErrorResources.ER_CANNOT_CMPL_EXTENSN, null), e); //"Could not compile extension", e);
}
}
/**
* Tests whether a certain function name is known within this namespace.
* @param function name of the function being tested
* @return true if its known, false if not.
*/
public boolean isFunctionAvailable(String function)
{
return (m_functions.get(function) != null);
}
/**
* Tests whether a certain element name is known within this namespace.
* @param element name of the element being tested
* @return true if its known, false if not.
*/
public boolean isElementAvailable(String element)
{
return (m_elements.get(element) != null);
}
/**
* Process a call to a function.
*
* @param funcName Function name.
* @param args The arguments of the function call.
* @param methodKey A key that uniquely identifies this class and method call.
* @param exprContext The context in which this expression is being executed.
*
* @return the return value of the function evaluation.
*
* @throws javax.xml.transform.TransformerException if parsing trouble
*/
public Object callFunction(
String funcName, Vector args, Object methodKey, ExpressionContext exprContext)
throws TransformerException
{
Object[] argArray;
try
{
argArray = new Object[args.size()];
for (int i = 0; i < argArray.length; i++)
{
Object o = args.elementAt(i);
argArray[i] = (o instanceof XObject) ? ((XObject) o).object() : o;
o = argArray[i];
if(null != o && o instanceof DTMIterator)
{
argArray[i] = new DTMNodeList((DTMIterator)o);
}
}
if (m_engineCall == null) {
m_engineCall = m_engine.getClass().getMethod("call",
new Class[]{ Object.class, String.class, Object[].class });
}
return m_engineCall.invoke(m_engine,
new Object[]{ null, funcName, argArray });
}
catch (Exception e)
{
e.printStackTrace();
String msg = e.getMessage();
if (null != msg)
{
if (msg.startsWith("Stopping after fatal error:"))
{
msg = msg.substring("Stopping after fatal error:".length());
}
// System.out.println("Call to extension function failed: "+msg);
throw new TransformerException(e);
}
else
{
// Should probably make a TRaX Extension Exception.
throw new TransformerException(XSLMessages.createMessage(XSLTErrorResources.ER_CANNOT_CREATE_EXTENSN, new Object[]{funcName, e })); //"Could not create extension: " + funcName
//+ " because of: " + e);
}
}
}
/**
* Process a call to an XPath extension function
*
* @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 javax.xml.transform.TransformerException
*/
public Object callFunction(FuncExtFunction extFunction,
Vector args,
ExpressionContext exprContext)
throws TransformerException
{
return callFunction(extFunction.getFunctionName(), args,
extFunction.getMethodKey(), exprContext);
}
/**
* Process a call to this extension namespace via an element. As a side
* effect, the results are sent to the TransformerImpl's result tree.
*
* @param localPart Element name's local part.
* @param element The extension element being processed.
* @param transformer Handle to TransformerImpl.
* @param stylesheetTree The compiled stylesheet tree.
* @param methodKey A key that uniquely identifies this class and method call.
*
* @throws XSLProcessorException thrown if something goes wrong
* while running the extension handler.
* @throws MalformedURLException if loading trouble
* @throws FileNotFoundException if loading trouble
* @throws java.io.IOException if loading trouble
* @throws javax.xml.transform.TransformerException if parsing trouble
*/
public void processElement(
String localPart, ElemTemplateElement element, TransformerImpl transformer,
Stylesheet stylesheetTree, Object methodKey)
throws TransformerException, IOException
{
Object result = null;
XSLProcessorContext xpc = new XSLProcessorContext(transformer, stylesheetTree);
try
{
Vector argv = new Vector(2);
argv.addElement(xpc);
argv.addElement(element);
result = callFunction(localPart, argv, methodKey,
transformer.getXPathContext().getExpressionContext());
}
catch (XPathProcessorException e)
{
// e.printStackTrace ();
throw new TransformerException(e.getMessage(), e);
}
if (result != null)
{
xpc.outputToResultTree(stylesheetTree, result);
}
}
}