org.apache.druid.query.groupby.having.HavingSpecMetricComparator.java Source code

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Here is the source code for org.apache.druid.query.groupby.having.HavingSpecMetricComparator.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.druid.query.groupby.having;

import com.google.common.primitives.Doubles;
import com.google.common.primitives.Longs;
import org.apache.druid.java.util.common.ISE;
import org.apache.druid.query.aggregation.AggregatorFactory;

import java.math.BigDecimal;
import java.util.Map;
import java.util.regex.Pattern;

/**
 */
class HavingSpecMetricComparator {
    static final Pattern LONG_PAT = Pattern.compile("[-|+]?\\d+");

    static int compare(String aggregationName, Number value, Map<String, AggregatorFactory> aggregators,
            Object metricValueObj) {
        if (metricValueObj != null) {
            if (aggregators != null && aggregators.containsKey(aggregationName)) {
                metricValueObj = aggregators.get(aggregationName).finalizeComputation(metricValueObj);
            }

            if (metricValueObj instanceof Long || metricValueObj instanceof Integer) {
                // Cast int metrics to longs, it's fine since longs can represent all int values.
                long n = ((Number) metricValueObj).longValue();

                if (value instanceof Long || value instanceof Integer) {
                    return Longs.compare(n, value.longValue());
                } else if (value instanceof Double || value instanceof Float) {
                    // Invert the comparison since we're providing n, value backwards.
                    return -compareDoubleToLong(value.doubleValue(), n);
                } else {
                    throw new ISE("Number was[%s]?!?", value.getClass().getName());
                }
            } else if (metricValueObj instanceof Double || metricValueObj instanceof Float) {
                // Cast floats to doubles, it's fine since doubles can represent all float values.
                double n = ((Number) metricValueObj).doubleValue();

                if (value instanceof Long || value instanceof Integer) {
                    return compareDoubleToLong(n, value.longValue());
                } else if (value instanceof Double || value instanceof Float) {
                    return Doubles.compare(n, value.doubleValue());
                } else {
                    throw new ISE("Number was[%s]?!?", value.getClass().getName());
                }
            } else if (metricValueObj instanceof String) {
                String metricValueStr = (String) metricValueObj;
                if (LONG_PAT.matcher(metricValueStr).matches()) {
                    long l = Long.parseLong(metricValueStr);
                    return Long.compare(l, value.longValue());
                } else {
                    double d = Double.parseDouble(metricValueStr);
                    return Double.compare(d, value.doubleValue());
                }
            } else {
                throw new ISE("Unknown type of metric value: %s", metricValueObj);
            }
        } else {
            return Double.compare(0, value.doubleValue());
        }
    }

    private static int compareDoubleToLong(final double a, final long b) {
        // Use BigDecimal when comparing integers vs floating points, a convenient way to handle all cases (like
        // fractional values, values out of range of max long/max int) without worrying about them ourselves.
        return BigDecimal.valueOf(a).compareTo(BigDecimal.valueOf(b));
    }
}