/**************************************************************************************
* 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.lookup;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.client.EventPropertyGetter;
import com.espertech.esper.client.EventType;
import com.espertech.esper.epl.expression.ExprEvaluatorContext;
import com.espertech.esper.epl.join.table.PropertyIndexedEventTableSingle;
import com.espertech.esper.event.EventBeanUtility;
import java.util.Collection;
/**
* Index lookup strategy for subqueries.
*/
public class SubordIndexedTableLookupStrategySingleProp implements SubordTableLookupStrategy
{
private final String property;
/**
* Stream numbers to get key values from.
*/
protected final int keyStreamNum;
/**
* Index to look up in.
*/
protected final PropertyIndexedEventTableSingle index;
/**
* Getters to use to get key values.
*/
protected final EventPropertyGetter propertyGetter;
/**
* Ctor.
* @param eventTypes is the event types per stream
* @param keyStreamNum is the stream number per property
* @param property is the key properties
* @param index is the table carrying the data to lookup into
*/
public SubordIndexedTableLookupStrategySingleProp(boolean isNWOnTrigger, EventType[] eventTypes, int keyStreamNum, String property, PropertyIndexedEventTableSingle index)
{
this.keyStreamNum = keyStreamNum + (isNWOnTrigger ? 1 : 0); // for on-trigger the key will be provided in a {1,2,...} stream and not {0,...}
this.property = property;
this.index = index;
propertyGetter = EventBeanUtility.getAssertPropertyGetter(eventTypes, keyStreamNum, property);
}
/**
* Returns index to look up in.
* @return index to use
*/
public PropertyIndexedEventTableSingle getIndex()
{
return index;
}
public Collection<EventBean> lookup(EventBean[] eventsPerStream, ExprEvaluatorContext context)
{
Object key = getKey(eventsPerStream);
return index.lookup(key);
}
/**
* Get the index lookup keys.
* @param eventsPerStream is the events for each stream
* @return key object
*/
protected Object getKey(EventBean[] eventsPerStream)
{
EventBean event = eventsPerStream[keyStreamNum];
return propertyGetter.get(event);
}
public String toString()
{
return toQueryPlan();
}
public String toQueryPlan() {
return this.getClass().getSimpleName() + " property=" + property + " stream=" + keyStreamNum;
}
}