/**
* Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information regarding copyright ownership. Apereo
* 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 the
* following location:
*
* <p>http://www.apache.org/licenses/LICENSE-2.0
*
* <p>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.apereo.portal.character.stream;
import java.util.Collection;
import java.util.Deque;
import java.util.LinkedList;
import java.util.regex.MatchResult;
import javax.servlet.http.HttpServletRequest;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.EndElement;
import javax.xml.stream.events.StartElement;
import javax.xml.stream.events.XMLEvent;
import org.apereo.portal.character.stream.events.CharacterEvent;
/**
* Base implementation of CharacterEventSource that deals with reading the element data off the
* stream.
*
*/
public abstract class BasePlaceholderEventSource implements CharacterEventSource {
@Override
public void generateCharacterEvents(
HttpServletRequest servletRequest,
XMLEventReader eventReader,
StartElement event,
Collection<CharacterEvent> eventBuffer)
throws XMLStreamException {
this.generateCharacterEvents(servletRequest, event, eventBuffer);
this.readToEndElement(eventReader, event);
}
protected void generateCharacterEvents(
HttpServletRequest servletRequest,
StartElement event,
Collection<CharacterEvent> eventBuffer) {
throw new UnsupportedOperationException("Super class must implement this method");
}
@Override
public void generateCharacterEvents(
HttpServletRequest servletRequest,
MatchResult matchResult,
Collection<CharacterEvent> eventBuffer) {
throw new UnsupportedOperationException("Super class must implement this method");
}
/**
* Read {@link XMLEvent}s off the {@link XMLEventReader} until the corresponding {@link
* EndElement} is found.
*/
protected final void readToEndElement(XMLEventReader eventReader, StartElement event)
throws XMLStreamException {
final Deque<QName> elementStack = new LinkedList<QName>();
elementStack.push(event.getName());
while (!elementStack.isEmpty()) {
final XMLEvent nextEvent = eventReader.nextEvent();
if (nextEvent.isStartElement()) {
final StartElement startElement = nextEvent.asStartElement();
elementStack.push(startElement.getName());
} else if (nextEvent.isEndElement()) {
final QName lastStart = elementStack.pop();
final EndElement endElement = nextEvent.asEndElement();
if (!lastStart.equals(endElement.getName())) {
throw new XMLStreamException(
"Invalid XML Structure, expected EndElement "
+ lastStart
+ " but found EndElment "
+ endElement.getName());
}
}
}
}
}