FilterParamIndexStringRange.java

/*
 * *************************************************************************************
 *  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.filter;

import com.espertech.esper.client.EventBean;
import com.espertech.esper.client.EventPropertyGetter;
import com.espertech.esper.client.EventType;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.util.*;

/**
 * Index for filter parameter constants for the range operators (range open/closed/half).
 * The implementation is based on the SortedMap implementation of TreeMap and stores only expression
 * parameter values of type DoubleRange.
 */
public final class FilterParamIndexStringRange extends FilterParamIndexStringRangeBase
{
    public FilterParamIndexStringRange(FilterSpecLookupable lookupable, FilterOperator filterOperator) {
        super(lookupable, filterOperator);

        if (!(filterOperator.isRangeOperator()))
        {
            throw new IllegalArgumentException("Invalid filter operator " + filterOperator);
        }
    }

    public final void matchEvent(EventBean theEvent, Collection<FilterHandle> matches)
    {
        Object objAttributeValue = lookupable.getGetter().get(theEvent);

        if (objAttributeValue == null)
        {
            return;
        }
        
        String attributeValue = (String) objAttributeValue;

        StringRange rangeStart = new StringRange(null, attributeValue);
        StringRange rangeEnd = new StringRange(attributeValue, null);
        SortedMap<StringRange, EventEvaluator> subMap = ranges.subMap(rangeStart, true, rangeEnd, true);

        // For not including either endpoint
        // A bit awkward to duplicate the loop code, however better than checking the boolean many times over
        // This may be a bit of an early performance optimization - the optimizer after all may do this better
        if (this.getFilterOperator() == FilterOperator.RANGE_OPEN)  // include neither endpoint
        {
            for (Map.Entry<StringRange, EventEvaluator> entry : subMap.entrySet())
            {
                if (entry.getKey().getMin().compareTo(attributeValue) < 0 && entry.getKey().getMax().compareTo(attributeValue) > 0) {
                    entry.getValue().matchEvent(theEvent, matches);
                }
            }
        }
        else if (this.getFilterOperator() == FilterOperator.RANGE_CLOSED)   // include all endpoints
        {
            for (Map.Entry<StringRange, EventEvaluator> entry : subMap.entrySet())
            {
                if (entry.getKey().getMin().compareTo(attributeValue) <= 0 && entry.getKey().getMax().compareTo(attributeValue) >= 0) {
                    entry.getValue().matchEvent(theEvent, matches);
                }
            }
        }
        else if (this.getFilterOperator() == FilterOperator.RANGE_HALF_CLOSED) // include high endpoint not low endpoint
        {
            for (Map.Entry<StringRange, EventEvaluator> entry : subMap.entrySet())
            {
                if (entry.getKey().getMin().compareTo(attributeValue) < 0 && entry.getKey().getMax().compareTo(attributeValue) >= 0) {
                    entry.getValue().matchEvent(theEvent, matches);
                }
            }
        }
        else if (this.getFilterOperator() == FilterOperator.RANGE_HALF_OPEN) // include low endpoint not high endpoint
        {
            for (Map.Entry<StringRange, EventEvaluator> entry : subMap.entrySet())
            {
                if (entry.getKey().getMin().compareTo(attributeValue) <= 0 && entry.getKey().getMax().compareTo(attributeValue) > 0) {
                    entry.getValue().matchEvent(theEvent, matches);
                }
            }
        }
        else
        {
            throw new IllegalStateException("Invalid filter operator " + this.getFilterOperator());
        }
    }

    private static final Log log = LogFactory.getLog(FilterParamIndexStringRange.class);
}