src/org/apache/xalan/extensions/ExtensionHandlerGeneral.java - xalan-j - Git at Google

 /*
  * 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.
  */
 /*
  * $Id$
  */
 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 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 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.get(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 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 IOException           if loading trouble
    * @throws 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.add(xpc);
       argv.add(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);
     }
   }
 }
	/*
	* 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.
	*/
	/*
	* $Id$
	*/
	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 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 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.get(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 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 IOException if loading trouble
	* @throws 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.add(xpc);
	argv.add(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);
	}
	}
	}