code: /*
   * #%L
   * Simmetrics Core
   * %%
   * Copyright (C) 2014 - 2016 Simmetrics Authors
   * %%
   * Licensed 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.
   * #L%
   */
  package org.simmetrics.metrics;
  
  import java.io.PrintWriter;
  import java.util.Set;
  
  import org.junit.Test;
  
  import com.google.caliper.Benchmark;
  import com.google.caliper.Param;
  import com.google.caliper.runner.CaliperMain;
  import com.google.common.collect.HashMultiset;
  import com.google.common.collect.Multiset;
  import com.google.common.collect.Multisets;
  import com.google.common.collect.Sets;
  
  @SuppressWarnings("javadoc")
  public class MathCaliper {
  
  	enum Value {
  		A1k(1000), A2k(2000), A5k(5000);
  
  		final Multiset<String> multiset;
  		final Set<String> set;
  		Value(int n) {
  			multiset = HashMultiset.create(n);
  			set = Sets.newHashSet();
  			for (int i = 0; i < n; i++) {
  				multiset.add("sheep" + i);
  				set.add("sheep" + i);
  			}
  		}
  	}
  
  	enum Method {
  
  		GUAVA {
  			@Override
  			public Multiset<String> union(Multiset<String> a, Multiset<String> b) {
  				return Multisets.union(a, b);
  			}
  
  			@Override
  			public Multiset<String> intersection(Multiset<String> a,
  					Multiset<String> b) {
  				return Multisets.intersection(a, b);
  			}
  
  			@Override
  			public Set<String> intersection(Set<String> a, Set<String> b) {
  				return Sets.intersection(a, b);
  			}
  		},
  		SIMMETRICS {
  
  			@Override
  			public Multiset<String> union(Multiset<String> a, Multiset<String> b) {
  				return Math.union(a, b);
  			}
  
  			@Override
  			public Multiset<String> intersection(Multiset<String> a,
  					Multiset<String> b) {
  				return Math.intersection(a, b);
  			}
  
  			@Override
  			public Set<String> intersection(Set<String> a, Set<String> b) {
  				return Math.intersection(a, b);
  			}
  
  		};
  
  		public abstract Multiset<String> union(Multiset<String> a, Multiset<String> b);
  		
  		public abstract Multiset<String> intersection(Multiset<String> a, Multiset<String> b);
  
  		public abstract Set<String> intersection(Set<String> a, Set<String> b);
  
  	}
  
  	@Param
  	Value a;
  
  	@Param
  	Value b;
  
  	@Param
  	Method method;
  
  	@Benchmark
  	int unionOfMultisetsEntrySetSize(int reps) {
  		final Method method = this.method;
  
  		int dummy = 0;
  		for (int i = 0; i < reps; i++) {
  			dummy += method.union(a.multiset, b.multiset).entrySet().size();
  		}
  		return dummy;
  	}
  
  	@Benchmark
  	int unionOfMultisetsElementSetSize(int reps) {
  		final Method method = this.method;
  
  		int dummy = 0;
  		for (int i = 0; i < reps; i++) {
  			dummy += method.union(a.multiset, b.multiset).elementSet().size();
  		}
  		return dummy;
  	}
  	
  	@Benchmark
  	int intersectionOfMultisetsEntrySetSize(int reps) {
  		final Method method = this.method;
  
  		int dummy = 0;
  		for (int i = 0; i < reps; i++) {
  			dummy += method.intersection(a.multiset, b.multiset).entrySet().size();
  		}
  		return dummy;
  	}
  
  	@Benchmark
  	int intersectionOfMultisetsElementSetSize(int reps) {
  		final Method method = this.method;
  
  		int dummy = 0;
  		for (int i = 0; i < reps; i++) {
  			dummy += method.intersection(a.multiset, b.multiset).elementSet().size();
  		}
  		return dummy;
  	}
  	
  	@Benchmark
  	int intersectionOfSetsSize(int reps) {
  		final Method method = this.method;
  
  		int dummy = 0;
  		for (int i = 0; i < reps; i++) {
  			dummy += method.intersection(a.set, b.set).size();
  		}
  		return dummy;
  	}
  
  	public static void main(String[] args) {
  		CaliperMain.main(MathCaliper.class, args);
  	}
  
  	@Test
  	public void dryrun() throws Exception {
  		PrintWriter stdout = new PrintWriter(System.out, true);
  		PrintWriter stderr = new PrintWriter(System.err, true);
  		String[] args = new String[] { "--dry-run", MathCaliper.class.getName() };
  		CaliperMain.exitlessMain(args, stdout, stderr);
  	}
  
  }
  