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* 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.
******************************************************************************/
package org.apache.olingo.odata2.core.ep.consumer;
import java.util.ArrayList;
import java.util.List;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import org.apache.olingo.odata2.api.edm.Edm;
import org.apache.olingo.odata2.api.edm.EdmEntitySet;
import org.apache.olingo.odata2.api.ep.EntityProviderException;
import org.apache.olingo.odata2.core.ep.util.FormatXml;
/**
*
*/
public class XmlLinkConsumer {
/**
* Reads single link with format {@code <uri>http://somelink</uri>}.
* @param reader
* @param entitySet
* @return link as string object
* @throws EntityProviderException
*/
public String readLink(final XMLStreamReader reader, final EdmEntitySet entitySet) throws EntityProviderException {
try {
reader.next();
return readLink(reader);
} catch (final XMLStreamException e) {
throw new EntityProviderException(EntityProviderException.EXCEPTION_OCCURRED.addContent(e.getClass()
.getSimpleName()), e);
}
}
private String readLink(final XMLStreamReader reader) throws XMLStreamException {
return readTag(reader, Edm.NAMESPACE_D_2007_08, FormatXml.D_URI);
}
private String readTag(final XMLStreamReader reader, final String namespaceURI, final String localName)
throws XMLStreamException {
reader.require(XMLStreamConstants.START_ELEMENT, namespaceURI, localName);
final String result = reader.getElementText();
reader.require(XMLStreamConstants.END_ELEMENT, namespaceURI, localName);
return result;
}
/**
* Reads multiple links with format
* <pre> {@code
* <links>
* <uri>http://somelink</uri>
* <uri>http://anotherLink</uri>
* <uri>http://somelink/yetAnotherLink</uri>
* </links>
* } </pre>
* @param reader
* @param entitySet
* @return list of string based links
* @throws EntityProviderException
*/
public List<String> readLinks(final XMLStreamReader reader, final EdmEntitySet entitySet)
throws EntityProviderException {
try {
List<String> links = new ArrayList<String>();
reader.nextTag();
reader.require(XMLStreamConstants.START_ELEMENT, Edm.NAMESPACE_D_2007_08, FormatXml.D_LINKS);
reader.nextTag();
while (!reader.isEndElement()) {
if (reader.getLocalName().equals(FormatXml.M_COUNT)) {
readTag(reader, Edm.NAMESPACE_M_2007_08, FormatXml.M_COUNT);
} else {
final String link = readLink(reader);
links.add(link);
}
reader.nextTag();
}
reader.require(XMLStreamConstants.END_ELEMENT, Edm.NAMESPACE_D_2007_08, FormatXml.D_LINKS);
return links;
} catch (final XMLStreamException e) {
throw new EntityProviderException(EntityProviderException.EXCEPTION_OCCURRED.addContent(e.getClass()
.getSimpleName()), e);
}
}
}