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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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package javax.xml.transform.stax;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.events.XMLEvent;
import javax.xml.transform.Source;
/**
* <p>Acts as a holder for an XML {@link Source} in the
* form of a StAX reader,i.e.
* {@link XMLStreamReader} or {@link XMLEventReader}.
* <code>StAXSource</code> can be used in all cases that accept
* a <code>Source</code>, e.g. {@link javax.xml.transform.Transformer},
* {@link javax.xml.validation.Validator} which accept
* <code>Source</code> as input.
*
* <p><code>StAXSource</code>s are consumed during processing
* and are not reusable.</p>
*
* @author <a href="mailto:Neeraj.Bajaj@Sun.com">Neeraj Bajaj</a>
* @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
*
* @see <a href="http://jcp.org/en/jsr/detail?id=173">
* JSR 173: Streaming API for XML</a>
* @see XMLStreamReader
* @see XMLEventReader
*
* @since 1.6
*/
public class StAXSource implements Source {
/** If {@link javax.xml.transform.TransformerFactory#getFeature(String name)}
* returns true when passed this value as an argument,
* the Transformer supports Source input of this type.
*/
public static final String FEATURE =
"http://javax.xml.transform.stax.StAXSource/feature";
/** <p><code>XMLEventReader</code> to be used for source input.</p> */
private XMLEventReader xmlEventReader = null;
/** <p><code>XMLStreamReader</code> to be used for source input.</p> */
private XMLStreamReader xmlStreamReader = null;
/** <p>System identifier of source input.</p> */
private String systemId = null;
/**
* <p>Creates a new instance of a <code>StAXSource</code>
* by supplying an {@link XMLEventReader}.</p>
*
* <p><code>XMLEventReader</code> must be a
* non-<code>null</code> reference.</p>
*
* <p><code>XMLEventReader</code> must be in
* {@link XMLStreamConstants#START_DOCUMENT} or
* {@link XMLStreamConstants#START_ELEMENT} state.</p>
*
* @param xmlEventReader <code>XMLEventReader</code> used to create
* this <code>StAXSource</code>.
*
* @throws XMLStreamException If <code>xmlEventReader</code> access
* throws an <code>Exception</code>.
* @throws IllegalArgumentException If <code>xmlEventReader</code> ==
* <code>null</code>.
* @throws IllegalStateException If <code>xmlEventReader</code>
* is not in <code>XMLStreamConstants.START_DOCUMENT</code> or
* <code>XMLStreamConstants.START_ELEMENT</code> state.
*/
public StAXSource(final XMLEventReader xmlEventReader)
throws XMLStreamException {
if (xmlEventReader == null) {
throw new IllegalArgumentException(
"StAXSource(XMLEventReader) with XMLEventReader == null");
}
// TODO: This is ugly ...
// there is no way to know the current position(event) of
// XMLEventReader. peek() is the only way to know the next event.
// The next event on the input stream should be
// XMLStreamConstants.START_DOCUMENT or
// XMLStreamConstants.START_ELEMENT.
XMLEvent event = xmlEventReader.peek();
int eventType = event.getEventType();
if (eventType != XMLStreamConstants.START_DOCUMENT
&& eventType != XMLStreamConstants.START_ELEMENT) {
throw new IllegalStateException(
"StAXSource(XMLEventReader) with XMLEventReader "
+ "not in XMLStreamConstants.START_DOCUMENT or "
+ "XMLStreamConstants.START_ELEMENT state");
}
this.xmlEventReader = xmlEventReader;
systemId = event.getLocation().getSystemId();
}
/**
* <p>Creates a new instance of a <code>StAXSource</code>
* by supplying an {@link XMLStreamReader}.</p>
*
* <p><code>XMLStreamReader</code> must be a
* non-<code>null</code> reference.</p>
*
* <p><code>XMLStreamReader</code> must be in
* {@link XMLStreamConstants#START_DOCUMENT} or
* {@link XMLStreamConstants#START_ELEMENT} state.</p>
*
* @param xmlStreamReader <code>XMLStreamReader</code> used to create
* this <code>StAXSource</code>.
*
* @throws IllegalArgumentException If <code>xmlStreamReader</code> ==
* <code>null</code>.
* @throws IllegalStateException If <code>xmlStreamReader</code>
* is not in <code>XMLStreamConstants.START_DOCUMENT</code> or
* <code>XMLStreamConstants.START_ELEMENT</code> state.
*/
public StAXSource(final XMLStreamReader xmlStreamReader) {
if (xmlStreamReader == null) {
throw new IllegalArgumentException(
"StAXSource(XMLStreamReader) with XMLStreamReader == null");
}
int eventType = xmlStreamReader.getEventType();
if (eventType != XMLStreamConstants.START_DOCUMENT
&& eventType != XMLStreamConstants.START_ELEMENT) {
throw new IllegalStateException(
"StAXSource(XMLStreamReader) with XMLStreamReader"
+ "not in XMLStreamConstants.START_DOCUMENT or "
+ "XMLStreamConstants.START_ELEMENT state");
}
this.xmlStreamReader = xmlStreamReader;
systemId = xmlStreamReader.getLocation().getSystemId();
}
/**
* <p>Get the <code>XMLEventReader</code> used by this
* <code>StAXSource</code>.</p>
*
* <p><code>XMLEventReader</code> will be <code>null</code>.
* if this <code>StAXSource</code> was created with a
* <code>XMLStreamReader</code>.</p>
*
* @return <code>XMLEventReader</code> used by this
* <code>StAXSource</code>.
*/
public XMLEventReader getXMLEventReader() {
return xmlEventReader;
}
/**
* <p>Get the <code>XMLStreamReader</code> used by this
* <code>StAXSource</code>.</p>
*
* <p><code>XMLStreamReader</code> will be <code>null</code>
* if this <code>StAXSource</code> was created with a
* <code>XMLEventReader</code>.</p>
*
* @return <code>XMLStreamReader</code> used by this
* <code>StAXSource</code>.
*/
public XMLStreamReader getXMLStreamReader() {
return xmlStreamReader;
}
/**
* <p>In the context of a <code>StAXSource</code>, it is not appropriate
* to explicitly set the system identifier.
* The <code>XMLStreamReader</code> or <code>XMLEventReader</code>
* used to construct this <code>StAXSource</code> determines the
* system identifier of the XML source.</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(
"StAXSource#setSystemId(systemId) cannot set the "
+ "system identifier for a StAXSource");
}
/**
* <p>Get the system identifier used by this
* <code>StAXSource</code>.</p>
*
* <p>The <code>XMLStreamReader</code> or <code>XMLEventReader</code>
* used to construct this <code>StAXSource</code> is queried to determine
* the system identifier of the XML source.</p>
*
* <p>The system identifier may be <code>null</code> or
* an empty <code>""</code> <code>String</code>.</p>
*
* @return System identifier used by this <code>StAXSource</code>.
*/
public String getSystemId() {
return systemId;
}
}