http://xml.apache.org/commons/components/external/: xml-commons provides an Apache-hosted set of DOM, SAX, and JAXP interfaces for use in other xml-based projects. Our hope is that we can standardize on both a common version and packaging scheme for these critical XML standards interfaces to make the lives of both our developers and users easier. The External Components portion of xml-commons contains interfaces that are defined by external standards organizations. For DOM, that's the W3C; for SAX it's David Megginson and sax.sourceforge.net; for JAXP it's Sun. 
/*
 * 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: XMLOutputFactory.java 670283 2008-06-22 01:04:09Z mrglavas $

package javax.xml.stream;

import java.io.OutputStream;
import java.io.Writer;

public abstract class XMLOutputFactory {

    public static final String IS_REPAIRING_NAMESPACES = "javax.xml.stream.isRepairingNamespaces";

    private static final String PROPERTY_NAME = "javax.xml.stream.XMLOutputFactory";
    private static final String DEFAULT_FACTORY = "com.ctc.wstx.stax.WstxOutputFactory";

    protected XMLOutputFactory() {}

    public static XMLOutputFactory newInstance()
        throws FactoryConfigurationError {
        try {
            return (XMLOutputFactory) FactoryFinder.find(PROPERTY_NAME, DEFAULT_FACTORY);
        }
        catch (FactoryFinder.ConfigurationError e) {
            throw new FactoryConfigurationError(e.getException(), e.getMessage());
        }
    }

    public static XMLInputFactory newInstance(String factoryId,
            ClassLoader classLoader) throws FactoryConfigurationError {
        if (classLoader == null) {
            classLoader = SecuritySupport.getContextClassLoader();
        }
        try {
            return (XMLInputFactory) FactoryFinder.find(factoryId, 
                    classLoader, "com.ctc.wstx.stax.WstxInputFactory");
        }
        catch (FactoryFinder.ConfigurationError e) {
            throw new FactoryConfigurationError(e.getException(), e.getMessage());
        }
    }

    public abstract XMLStreamWriter createXMLStreamWriter(Writer stream)
    throws XMLStreamException;

    public abstract XMLStreamWriter createXMLStreamWriter(
            OutputStream stream) throws XMLStreamException;

    public abstract XMLStreamWriter createXMLStreamWriter(
            OutputStream stream, String encoding)
    throws XMLStreamException;

    public abstract XMLStreamWriter createXMLStreamWriter(
            javax.xml.transform.Result result) throws XMLStreamException;

    public abstract XMLEventWriter createXMLEventWriter(
            javax.xml.transform.Result result) throws XMLStreamException;

    public abstract XMLEventWriter createXMLEventWriter(
            OutputStream stream) throws XMLStreamException;

    public abstract XMLEventWriter createXMLEventWriter(
            OutputStream stream, String encoding)
    throws XMLStreamException;

    public abstract XMLEventWriter createXMLEventWriter(Writer stream)
    throws XMLStreamException;

    public abstract void setProperty(String name, Object value)
    throws IllegalArgumentException;

    public abstract Object getProperty(String name)
    throws IllegalArgumentException;

    public abstract boolean isPropertySupported(String name);
}