package org.apache.cassandra.stress.settings;
/*
*
* 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.
*
*/
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.commons.math3.distribution.ExponentialDistribution;
import org.apache.commons.math3.distribution.NormalDistribution;
import org.apache.commons.math3.distribution.UniformRealDistribution;
import org.apache.commons.math3.distribution.WeibullDistribution;
import org.apache.commons.math3.random.JDKRandomGenerator;
import org.apache.cassandra.stress.generate.Distribution;
import org.apache.cassandra.stress.generate.DistributionBoundApache;
import org.apache.cassandra.stress.generate.DistributionFactory;
import org.apache.cassandra.stress.generate.DistributionFixed;
import org.apache.cassandra.stress.generate.DistributionInverted;
import org.apache.cassandra.stress.generate.DistributionOffsetApache;
import org.apache.cassandra.stress.generate.RatioDistribution;
import org.apache.cassandra.stress.generate.RatioDistributionFactory;
/**
* For selecting a mathematical distribution
*/
public class OptionRatioDistribution extends Option
{
private static final Pattern FULL = Pattern.compile("(.*)/([0-9]+[KMB]?)", Pattern.CASE_INSENSITIVE);
final OptionDistribution delegate;
private double divisor;
private static final RatioDistribution DEFAULT = new RatioDistribution(new DistributionFixed(1), 1);
public OptionRatioDistribution(String prefix, String defaultSpec, String description)
{
delegate = new OptionDistribution(prefix, defaultSpec, description);
}
@Override
public boolean accept(String param)
{
Matcher m = FULL.matcher(param);
if (!m.matches() || !delegate.accept(m.group(1)))
return false;
divisor = OptionDistribution.parseLong(m.group(2));
return true;
}
public static RatioDistributionFactory get(String spec)
{
OptionRatioDistribution opt = new OptionRatioDistribution("", "", "");
if (!opt.accept(spec))
throw new IllegalArgumentException();
return opt.get();
}
public RatioDistributionFactory get()
{
return !delegate.setByUser() ? new DefaultFactory() : new DelegateFactory(delegate.get(), divisor);
}
@Override
public boolean happy()
{
return delegate.happy();
}
public String longDisplay()
{
return delegate.longDisplay();
}
@Override
public List<String> multiLineDisplay()
{
return Arrays.asList(
GroupedOptions.formatMultiLine("EXP(min..max)/divisor", "An exponential ratio distribution over the range [min..max]/divisor"),
GroupedOptions.formatMultiLine("EXTREME(min..max,shape)/divisor", "An extreme value (Weibull) ratio distribution over the range [min..max]/divisor"),
GroupedOptions.formatMultiLine("GAUSSIAN(min..max,stdvrng)/divisor", "A gaussian/normal ratio distribution, where mean=(min+max)/2, and stdev is ((mean-min)/stdvrng)/divisor"),
GroupedOptions.formatMultiLine("GAUSSIAN(min..max,mean,stdev)/divisor", "A gaussian/normal ratio distribution, with explicitly defined mean and stdev"),
GroupedOptions.formatMultiLine("UNIFORM(min..max)/divisor", "A uniform ratio distribution over the range [min, max]/divisor"),
GroupedOptions.formatMultiLine("FIXED(val)/divisor", "A fixed ratio distribution, always returning the same value"),
"Preceding the name with ~ will invert the distribution, e.g. ~exp(1..10)/10 will yield 0.1 least, instead of most, often",
"Aliases: extr, gauss, normal, norm, weibull"
);
}
boolean setByUser()
{
return delegate.setByUser();
}
@Override
public String shortDisplay()
{
return delegate.shortDisplay();
}
// factories
private static final class DefaultFactory implements RatioDistributionFactory
{
@Override
public RatioDistribution get()
{
return DEFAULT;
}
}
private static final class DelegateFactory implements RatioDistributionFactory
{
final DistributionFactory delegate;
final double divisor;
private DelegateFactory(DistributionFactory delegate, double divisor)
{
this.delegate = delegate;
this.divisor = divisor;
}
@Override
public RatioDistribution get()
{
return new RatioDistribution(delegate.get(), divisor);
}
}
@Override
public int hashCode()
{
return delegate.hashCode();
}
@Override
public boolean equals(Object that)
{
return super.equals(that) && ((OptionRatioDistribution) that).delegate.equals(this.delegate);
}
}