Java tutorial
/************************************************************************************** * 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 org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.util.Collection; import java.util.Map; import java.util.SortedMap; /** * 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 FilterParamIndexDoubleRange extends FilterParamIndexDoubleRangeBase { public FilterParamIndexDoubleRange(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; } double attributeValue = ((Number) objAttributeValue).doubleValue(); DoubleRange rangeStart = new DoubleRange(attributeValue - largestRangeValueDouble, attributeValue); DoubleRange rangeEnd = new DoubleRange(attributeValue, Double.MAX_VALUE); SortedMap<DoubleRange, EventEvaluator> subMap = ranges.subMap(rangeStart, rangeEnd); // 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<DoubleRange, EventEvaluator> entry : subMap.entrySet()) { if ((attributeValue > entry.getKey().getMin()) && (attributeValue < entry.getKey().getMax())) { entry.getValue().matchEvent(theEvent, matches); } } } else if (this.getFilterOperator() == FilterOperator.RANGE_CLOSED) // include all endpoints { for (Map.Entry<DoubleRange, EventEvaluator> entry : subMap.entrySet()) { if ((attributeValue >= entry.getKey().getMin()) && (attributeValue <= entry.getKey().getMax())) { entry.getValue().matchEvent(theEvent, matches); } } } else if (this.getFilterOperator() == FilterOperator.RANGE_HALF_CLOSED) // include high endpoint not low endpoint { for (Map.Entry<DoubleRange, EventEvaluator> entry : subMap.entrySet()) { if ((attributeValue > entry.getKey().getMin()) && (attributeValue <= entry.getKey().getMax())) { entry.getValue().matchEvent(theEvent, matches); } } } else if (this.getFilterOperator() == FilterOperator.RANGE_HALF_OPEN) // include low endpoint not high endpoint { for (Map.Entry<DoubleRange, EventEvaluator> entry : subMap.entrySet()) { if ((attributeValue >= entry.getKey().getMin()) && (attributeValue < entry.getKey().getMax())) { entry.getValue().matchEvent(theEvent, matches); } } } else { throw new IllegalStateException("Invalid filter operator " + this.getFilterOperator()); } } private static final Log log = LogFactory.getLog(FilterParamIndexDoubleRange.class); }