com.fasterxml.aalto.evt.EventAllocatorImpl Maven / Gradle / Ivy
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/* Aalto XML processor
*
* Copyright (c) 2006- Tatu Saloranta, [email protected]
*
* Licensed under the License specified in the file LICENSE which is
* included with the source code.
* You may not use this file except in compliance with the License.
*
* 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 com.fasterxml.aalto.evt;
import javax.xml.stream.*;
import javax.xml.stream.events.XMLEvent;
import javax.xml.stream.util.XMLEventAllocator;
import org.codehaus.stax2.ri.evt.Stax2EventAllocatorImpl;
import com.fasterxml.aalto.AsyncXMLStreamReader;
/**
* Specialized event allocator implementation. Beyond additions needed
* to support DTD entities, implements non-location-preserving optimization.
*
* @author Tatu Saloranta
*/
public final class EventAllocatorImpl
extends Stax2EventAllocatorImpl
{
final static EventAllocatorImpl sStdInstance = new EventAllocatorImpl(true);
/*
/**********************************************************************
/* Configuration
/**********************************************************************
*/
protected final boolean _cfgPreserveLocation;
/*
/**********************************************************************
/* Recycled objects
/**********************************************************************
*/
/**
* Last used location info; only relevant to non-accurate-location
* allocators.
*/
protected Location _lastLocation = null;
/**
* @param preserveLocation If true, allocator will construct instances
* that have accurate location information; if false, instances
* will only have some generic shared Location info. Latter option
* will reduce memory usage/thrashing a bit, and may improve speed.
*/
protected EventAllocatorImpl(boolean preserveLocation) {
_cfgPreserveLocation = preserveLocation;
}
public static EventAllocatorImpl getDefaultInstance() {
/* Standard allocator instance can be shared as it
* has no state.
*/
return sStdInstance;
}
public static EventAllocatorImpl getFastInstance() {
/* Can not share instances, due to QName caching, as well as because
* of Location object related state
*/
return new EventAllocatorImpl(false);
}
/**
* Default implementation assumes that the caller knows how to
* share instances, and so need not create new copies.
*
* Note: if this class is sub-classes, this method should be
* redefined if assumptions about shareability do not hold.
*/
@Override
public XMLEventAllocator newInstance() {
return new EventAllocatorImpl(_cfgPreserveLocation);
}
/*
/**********************************************************************
/* Overriden methods
/**********************************************************************
*/
@Override
public XMLEvent allocate(XMLStreamReader r) throws XMLStreamException
{
if (r.getEventType() == AsyncXMLStreamReader.EVENT_INCOMPLETE) {
return IncompleteEvent.instance();
}
return super.allocate(r);
}
/**
* Method used to get the {@link Location} object to use for
* an event to create. Base implementation just calls stream
* reader's accessors, but sub-classes may choose to use other
* methods (esp. when not in "preserve location" mode).
*/
@Override
protected Location getLocation(XMLStreamReader r)
{
if (_cfgPreserveLocation) {
return r.getLocation();
}
Location loc = _lastLocation;
/* And even if we can just share one instance, we need that
* first instance...
*/
if (loc == null) {
loc = _lastLocation = r.getLocation();
}
return loc;
}
// Should redefine this one:
/*
protected EntityReference createEntityReference(XMLStreamReader r, Location loc)
throws XMLStreamException
*/
// As well as this:
/*
protected DTD createDTD(XMLStreamReader r, Location loc)
throws XMLStreamException
*/
// And probably this one too?
/*
protected StartElement createStartElement(XMLStreamReader r, Location loc)
throws XMLStreamException
{
return super.createStartElement(r, loc);
}
*/
}