/**************************************************************************************
* 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.PropertyIndexedEventTable;
import java.util.Arrays;
import java.util.Collection;
/**
* Index lookup strategy for subqueries.
*/
public class SubordIndexedTableLookupStrategyProp implements SubordTableLookupStrategy
{
private final String[] properties;
/**
* Stream numbers to get key values from.
*/
protected final int[] keyStreamNums;
/**
* Index to look up in.
*/
protected final PropertyIndexedEventTable index;
/**
* Getters to use to get key values.
*/
protected final EventPropertyGetter[] propertyGetters;
/**
* Ctor.
* @param eventTypes is the event types per stream
* @param keyStreamNumbers is the stream number per property
* @param properties is the key properties
* @param index is the table carrying the data to lookup into
*/
public SubordIndexedTableLookupStrategyProp(boolean isNWOnTrigger, EventType[] eventTypes, int[] keyStreamNumbers, String[] properties, PropertyIndexedEventTable index)
{
this.keyStreamNums = keyStreamNumbers;
this.properties = properties;
this.index = index;
propertyGetters = new EventPropertyGetter[properties.length];
for (int i = 0; i < keyStreamNumbers.length; i++)
{
int streamNumber = keyStreamNumbers[i];
String property = properties[i];
EventType eventType = eventTypes[streamNumber];
propertyGetters[i] = eventType.getGetter(property);
if (propertyGetters[i] == null)
{
throw new IllegalArgumentException("Property named '" + properties[i] + "' is invalid for type " + eventType);
}
}
for (int i = 0; i < keyStreamNums.length; i++) {
keyStreamNums[i] += (isNWOnTrigger ? 1 : 0); // for on-trigger the key will be provided in a {1,2,...} stream and not {0,...}
}
}
/**
* Returns properties to use from lookup event to look up in index.
* @return properties to use from lookup event
*/
public String[] getProperties()
{
return properties;
}
/**
* Returns index to look up in.
* @return index to use
*/
public PropertyIndexedEventTable getIndex()
{
return index;
}
public Collection<EventBean> lookup(EventBean[] eventsPerStream, ExprEvaluatorContext context)
{
Object[] keys = getKeys(eventsPerStream);
return index.lookup(keys);
}
/**
* Get the index lookup keys.
* @param eventsPerStream is the events for each stream
* @return key object
*/
protected Object[] getKeys(EventBean[] eventsPerStream)
{
Object[] keyValues = new Object[propertyGetters.length];
for (int i = 0; i < propertyGetters.length; i++)
{
int streamNum = keyStreamNums[i];
EventBean event = eventsPerStream[streamNum];
keyValues[i] = propertyGetters[i].get(event);
}
return keyValues;
}
public String toString()
{
return toQueryPlan();
}
public String toQueryPlan() {
return this.getClass().getSimpleName() +
" indexProps=" + Arrays.toString(properties) +
" keyStreamNums=" + Arrays.toString(keyStreamNums);
}
}