/**************************************************************************************
* Copyright (C) 2008 EsperTech, Inc. All rights reserved. *
* http://esper.codehaus.org *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
**************************************************************************************/
package com.espertech.esper.epl.named;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.client.EventType;
import com.espertech.esper.collection.FlushedEventBuffer;
import com.espertech.esper.collection.OneEventCollection;
import com.espertech.esper.epl.expression.ExprEvaluator;
import com.espertech.esper.epl.expression.ExprEvaluatorContext;
import com.espertech.esper.epl.property.PropertyEvaluator;
import com.espertech.esper.util.StopCallback;
import com.espertech.esper.view.ViewSupport;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import java.util.Iterator;
/**
* Represents a consumer of a named window that selects from a named window via a from-clause.
* <p>
* The view simply dispatches directly to child views, and keeps the last new event for iteration.
*/
public class NamedWindowConsumerView extends ViewSupport implements StopCallback
{
private static final Log log = LogFactory.getLog(NamedWindowConsumerView.class);
private final ExprEvaluator[] filterList;
private final EventType eventType;
private final NamedWindowConsumerCallback consumerCallback;
private final ExprEvaluatorContext exprEvaluatorContext;
private final PropertyEvaluator optPropertyEvaluator;
private final FlushedEventBuffer optPropertyContainedBuffer;
/**
* Ctor.
* @param eventType the event type of the named window
* @param filterList is a list of filter expressions
* @param exprEvaluatorContext context for expression evalauation
*/
public NamedWindowConsumerView(ExprEvaluator[] filterList,
PropertyEvaluator optPropertyEvaluator,
EventType eventType,
NamedWindowConsumerCallback consumerCallback,
ExprEvaluatorContext exprEvaluatorContext)
{
this.filterList = filterList;
this.optPropertyEvaluator = optPropertyEvaluator;
if (optPropertyEvaluator != null) {
optPropertyContainedBuffer = new FlushedEventBuffer();
}
else {
optPropertyContainedBuffer = null;
}
this.eventType = eventType;
this.consumerCallback = consumerCallback;
this.exprEvaluatorContext = exprEvaluatorContext;
}
public void update(EventBean[] newData, EventBean[] oldData)
{
// if we have a filter for the named window,
if (filterList.length != 0)
{
EventBean[] eventPerStream = new EventBean[1];
newData = passFilter(newData, true, exprEvaluatorContext, eventPerStream);
oldData = passFilter(oldData, false, exprEvaluatorContext, eventPerStream);
}
if (optPropertyEvaluator != null) {
newData = getUnpacked(newData);
oldData = getUnpacked(oldData);
}
if ((newData != null) || (oldData != null))
{
updateChildren(newData, oldData);
}
}
private EventBean[] getUnpacked(EventBean[] data)
{
if (data == null) {
return null;
}
if (data.length == 0) {
return data;
}
for (int i = 0; i < data.length; i++) {
EventBean[] unpacked = optPropertyEvaluator.getProperty(data[i], exprEvaluatorContext);
optPropertyContainedBuffer.add(unpacked);
}
return optPropertyContainedBuffer.getAndFlush();
}
private EventBean[] passFilter(EventBean[] eventData, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext, EventBean[] eventPerStream)
{
if ((eventData == null) || (eventData.length == 0))
{
return null;
}
OneEventCollection filtered = null;
for (EventBean event : eventData)
{
eventPerStream[0] = event;
boolean pass = true;
for (ExprEvaluator filter : filterList)
{
Boolean result = (Boolean) filter.evaluate(eventPerStream, isNewData, exprEvaluatorContext);
if ((result != null) && (!result))
{
pass = false;
break;
}
}
if (pass)
{
if (filtered == null)
{
filtered = new OneEventCollection();
}
filtered.add(event);
}
}
if (filtered == null)
{
return null;
}
return filtered.toArray();
}
public EventType getEventType()
{
if (optPropertyEvaluator != null) {
return optPropertyEvaluator.getFragmentEventType();
}
return eventType;
}
public Iterator<EventBean> iterator()
{
return new FilteredEventIterator(filterList, consumerCallback.getIterator(), exprEvaluatorContext);
}
public void stop()
{
consumerCallback.stopped(this);
}
}