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 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package javax.xml.transform.stax;

import javax.xml.stream.XMLEventWriter;

import javax.xml.stream.XMLStreamWriter;

import javax.xml.transform.Result;

/**

 * <p>Acts as a holder for an XML {@link Result} in the

 * form of a StAX writer,i.e.

 * {@link XMLStreamWriter} or {@link XMLEventWriter}.

 * <code>StAXResult</code> can be used in all cases that accept

 * a <code>Result</code>, e.g. {@link javax.xml.transform.Transformer},

 * {@link javax.xml.validation.Validator} which accept

 * <code>Result</code> as input.

 *

 *

 * @see <a href="http://jcp.org/en/jsr/detail?id=173">

 *  JSR 173: Streaming API for XML</a>

 * @see XMLStreamWriter

 * @see XMLEventWriter

 *

 * @since 1.6

 */

public class StAXResult implements Result {

    /** If {@link javax.xml.transform.TransformerFactory#getFeature(String name)}

     * returns true when passed this value as an argument,

     * the Transformer supports Result output of this type.

     */

    public static final String FEATURE =

        "http://javax.xml.transform.stax.StAXResult/feature";

    /**

     * <p><code>XMLEventWriter</code> to be used for

     * <code>Result</code> output.</p>

     */

    private XMLEventWriter xmlEventWriter = null;

    /**

     * <p><code>XMLStreamWriter</code> to be used for

     * <code>Result</code> output.</p>

     */

    private XMLStreamWriter xmlStreamWriter = null;

    /** <p>System identifier for this <code>StAXResult</code>.<p> */

    private String systemId = null;

    /**

     * <p>Creates a new instance of a <code>StAXResult</code>

     * by supplying an {@link XMLEventWriter}.</p>

     *

     * <p><code>XMLEventWriter</code> must be a

     * non-<code>null</code> reference.</p>

     *

     * @param xmlEventWriter <code>XMLEventWriter</code> used to create

     *   this <code>StAXResult</code>.

     *

     * @throws IllegalArgumentException If <code>xmlEventWriter</code> ==

     *   <code>null</code>.

     */

    public StAXResult(final XMLEventWriter xmlEventWriter) {

        if (xmlEventWriter == null) {

            throw new IllegalArgumentException(

                    "StAXResult(XMLEventWriter) with XMLEventWriter == null");

        }

        this.xmlEventWriter = xmlEventWriter;

    }

    /**

     * <p>Creates a new instance of a <code>StAXResult</code>

     * by supplying an {@link XMLStreamWriter}.</p>

     *

     * <p><code>XMLStreamWriter</code> must be a

     * non-<code>null</code> reference.</p>

     *

     * @param xmlStreamWriter <code>XMLStreamWriter</code> used to create

     *   this <code>StAXResult</code>.

     *

     * @throws IllegalArgumentException If <code>xmlStreamWriter</code> ==

     *   <code>null</code>.

     */

    public StAXResult(final XMLStreamWriter xmlStreamWriter) {

        if (xmlStreamWriter == null) {

            throw new IllegalArgumentException(

                    "StAXResult(XMLStreamWriter) with XMLStreamWriter == null");

        }

        this.xmlStreamWriter = xmlStreamWriter;

    }

    /**

     * <p>Get the <code>XMLEventWriter</code> used by this

     * <code>StAXResult</code>.</p>

     *

     * <p><code>XMLEventWriter</code> will be <code>null</code>

     * if this <code>StAXResult</code> was created with a

     * <code>XMLStreamWriter</code>.</p>

     *

     * @return <code>XMLEventWriter</code> used by this

     *   <code>StAXResult</code>.

     */

    public XMLEventWriter getXMLEventWriter() {

        return xmlEventWriter;

    }

    /**

     * <p>Get the <code>XMLStreamWriter</code> used by this

     * <code>StAXResult</code>.</p>

     *

     * <p><code>XMLStreamWriter</code> will be <code>null</code>

     * if this <code>StAXResult</code> was created with a

     * <code>XMLEventWriter</code>.</p>

     *

     * @return <code>XMLStreamWriter</code> used by this

     *   <code>StAXResult</code>.

     */

    public XMLStreamWriter getXMLStreamWriter() {

        return xmlStreamWriter;

    }

    /**

     * <p>In the context of a <code>StAXResult</code>, it is not appropriate

     * to explicitly set the system identifier.

     * The <code>XMLEventWriter</code> or <code>XMLStreamWriter</code>

     * used to construct this <code>StAXResult</code> determines the

     * system identifier of the XML result.</p>

     *

     * <p>An {@link UnsupportedOperationException} is <strong>always</strong>

     * thrown by this method.</p>

     *

     * @param systemId Ignored.

     *

     * @throws UnsupportedOperationException Is <strong>always</strong>

     *   thrown by this method.

     */

    public void setSystemId(final String systemId) {

        throw new UnsupportedOperationException(

                "StAXResult#setSystemId(systemId) cannot set the "

                + "system identifier for a StAXResult");

    }

    /**

     * <p>The returned system identifier is always <code>null</code>.</p>

     *

     * @return The returned system identifier is always <code>null</code>.

     */

    public String getSystemId() {

        return null;

    }

}