/*
* @(#)$Id: TemplatesImpl.java,v 1.9 2001/11/29 09:33:35 morten Exp $
*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2001 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 2001, Sun
* Microsystems., http://www.sun.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* @author Morten Jorgensen
* @author G. Todd Millerj
* @author Jochen Cordes <Jochen.Cordes@t-online.de>
*
*/
package org.apache.xalan.xsltc.trax;
import java.io.Serializable;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.io.IOException;
import java.util.Properties;
import java.security.AccessController;
import java.security.PrivilegedAction;
import javax.xml.transform.*;
import org.apache.xalan.xsltc.Translet;
import org.apache.xalan.xsltc.compiler.*;
import org.apache.xalan.xsltc.runtime.*;
import org.apache.xalan.xsltc.compiler.util.ErrorMsg;
public final class TemplatesImpl implements Templates, Serializable {
// Contains the name of the main translet class
private String _name = null;
// Contains the actual class definition for the translet class and
// any auxiliary classes (representing node sort records, predicates, etc.)
private byte[][] _bytecodes = null;
// Contains the translet class definition(s). These are created when this
// Templates is first instanciated or read back from disk (see readObject())
private Class[] _class = null;
// This tells us which index the main translet class has in the _class
// and _bytecodes arrays (above).
private int _transletIndex = -1;
// Our own private class loader - builds Class definitions from bytecodes
private class TransletClassLoader extends ClassLoader {
protected TransletClassLoader(ClassLoader parent){
super(parent);
}
public Class defineClass(byte[] b) {
return super.defineClass(null, b, 0, b.length);
}
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(_name);
out.writeObject(_bytecodes);
out.flush();
}
public void readExternal(ObjectInput in)
throws IOException, ClassNotFoundException {
_name = (String)in.readObject();
_bytecodes = (byte[][])in.readObject();
_class = null; // must be created again...
}
/**
* The only way to create an XSLTC emplate object
* The bytecodes for the translet and auxiliary classes, plus the name of
* the main translet class, must be supplied
*/
protected TemplatesImpl(byte[][] bytecodes, String transletName) {
_bytecodes = bytecodes;
_name = transletName;
}
/**
* The TransformerFactory must pass us the translet bytecodes using this
* method before we can create any translet instances
*/
protected void setTransletBytecodes(byte[][] bytecodes) {
_bytecodes = bytecodes;
}
/**
* Returns the translet bytecodes stored in this template
*/
protected byte[][] getTransletBytecodes() {
return(_bytecodes);
}
/**
* The TransformerFactory should call this method to set the translet name
*/
protected void setTransletName(String name) {
_name = name;
}
/**
* Returns the name of the main translet class stored in this template
*/
protected String getTransletName() {
return _name;
}
/**
* Defines the translet class and auxiliary classes.
* Returns a reference to the Class object that defines the main class
*/
private void defineTransletClasses()
throws TransformerConfigurationException {
if (_bytecodes == null) {
ErrorMsg err = new ErrorMsg(ErrorMsg.NO_TRANSLET_CLASS_ERR);
throw new TransformerConfigurationException(err.toString());
}
TransletClassLoader loader =
(TransletClassLoader) AccessController.doPrivileged(
new PrivilegedAction() {
public Object run() {
ClassLoader current = getClass().getClassLoader();
return new TransletClassLoader(current);
}
}
);
try {
final int classCount = _bytecodes.length;
_class = new Class[classCount];
for (int i = 0; i < classCount; i++) {
_class[i] = loader.defineClass(_bytecodes[i]);
if (_class[i].getName().equals(_name))
_transletIndex = i;
}
if (_transletIndex < 0) {
ErrorMsg err= new ErrorMsg(ErrorMsg.NO_MAIN_TRANSLET_ERR,_name);
throw new TransformerConfigurationException(err.toString());
}
}
catch (ClassFormatError e) {
ErrorMsg err = new ErrorMsg(ErrorMsg.TRANSLET_CLASS_ERR+_name);
throw new TransformerConfigurationException(err.toString());
}
catch (LinkageError e) {
ErrorMsg err = new ErrorMsg(ErrorMsg.TRANSLET_OBJECT_ERR+_name);
throw new TransformerConfigurationException(err.toString());
}
}
/**
* This method generates an instance of the translet class that is
* wrapped inside this Template. The translet instance will later
* be wrapped inside a Transformer object.
*/
private Translet getTransletInstance()
throws TransformerConfigurationException {
try {
if (_name == null) return null;
if (_class == null) defineTransletClasses();
// The translet needs a reference to all its auxiliary class
// definitions so that it can instanciate them on the fly. You
// wouldn't think this is necessary, but it seems like the JVM
// quickly forgets the classes we define here and the translet
// needs to know them as long as it exists.
Translet translet = (Translet)_class[_transletIndex].newInstance();
final int classCount = _bytecodes.length;
for (int i = 0; i < classCount; i++) {
if (i != _transletIndex)
translet.addAuxiliaryClass(_class[i]);
}
return translet;
}
catch (InstantiationException e) {
ErrorMsg err = new ErrorMsg(ErrorMsg.TRANSLET_OBJECT_ERR+_name);
throw new TransformerConfigurationException(err.toString());
}
catch (IllegalAccessException e) {
ErrorMsg err = new ErrorMsg(ErrorMsg.TRANSLET_OBJECT_ERR+_name);
throw new TransformerConfigurationException(err.toString());
}
}
/**
* Implements JAXP's Templates.newTransformer()
*
* @throws TransformerConfigurationException
*/
public Transformer newTransformer()
throws TransformerConfigurationException {
return(new TransformerImpl(getTransletInstance()));
}
/**
* Implements JAXP's Templates.getOutputProperties()
*/
public Properties getOutputProperties() {
// We need to instanciate a translet to get the output settings, so
// we might as well just instanciate a Transformer and use its
// implementation of this method
try {
Transformer transformer = newTransformer();
return transformer.getOutputProperties();
}
catch (TransformerConfigurationException e) {
return null;
}
}
}