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Complex event processing and event series analysis component

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/**************************************************************************************
 * 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.view;

import com.espertech.esper.client.EventType;

import java.util.List;

/**
 * Holder for the logical chain of view factories.
 */
public class ViewFactoryChain
{
    private List viewFactoryChain;
    private EventType streamEventType;

    /**
     * Ctor.
     * @param streamEventType is the event type of the event stream
     * @param viewFactoryChain is the chain of view factories
     */
    public ViewFactoryChain(EventType streamEventType, List viewFactoryChain)
    {
        this.streamEventType = streamEventType;
        this.viewFactoryChain = viewFactoryChain;
    }

    /**
     * Returns the final event type which is the event type of the last view factory in the chain,
     * or if the chain is empty then the stream's event type.
     * @return final event type of the last view or stream
     */
    public EventType getEventType()
    {
        if (viewFactoryChain.isEmpty())
        {
            return streamEventType;
        }
        else
        {
            return viewFactoryChain.get(viewFactoryChain.size() - 1).getEventType();
        }
    }

    /**
     * Returns the chain of view factories.
     * @return view factory list
     */
    public List getViewFactoryChain()
    {
        return viewFactoryChain;
    }

    /**
     * Returns the number of data window factories for the chain.
     * @return number of data window factories
     */
    public int getDataWindowViewFactoryCount()
    {
        int count = 0;
        for (ViewFactory chainElement : viewFactoryChain) {
            if (chainElement instanceof DataWindowViewFactory)
            {
                count++;
            }
        }
        return count;
    }
}