/*
* Copyright (C) 2011 Clearspring Technologies, Inc.
*
* 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.
*/
package com.clearspring.analytics.stream;
import java.util.Arrays;
import java.util.List;
import org.junit.Test;
import cern.jet.random.Distributions;
import cern.jet.random.engine.RandomEngine;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
public class TestConcurrentStreamSummary {
private static final int NUM_ITERATIONS = 100000;
@Test
public void testStreamSummary() {
ConcurrentStreamSummary<String> vs = new ConcurrentStreamSummary<String>(3);
String[] stream = {"X", "X", "Y", "Z", "A", "B", "C", "X", "X", "A", "A", "A"};
for (String i : stream) {
vs.offer(i);
/*
for(String s : vs.poll(3))
System.out.print(s+" ");
*/
System.out.println(vs);
}
}
@Test
public void testTopK() {
ConcurrentStreamSummary<String> vs = new ConcurrentStreamSummary<String>(3);
String[] stream = {"X", "X", "Y", "Z", "A", "B", "C", "X", "X", "A", "C", "A", "A"};
for (String i : stream) {
vs.offer(i);
}
List<ScoredItem<String>> topK = vs.peekWithScores(3);
for (ScoredItem<String> c : topK) {
assertTrue(Arrays.asList("A", "C", "X").contains(c.getItem()));
}
}
@Test
public void testTopKWithIncrement() {
ConcurrentStreamSummary<String> vs = new ConcurrentStreamSummary<String>(3);
String[] stream = {"X", "X", "Y", "Z", "A", "B", "C", "X", "X", "A", "C", "A", "A"};
for (String i : stream) {
vs.offer(i, 10);
}
List<ScoredItem<String>> topK = vs.peekWithScores(3);
for (ScoredItem<String> c : topK) {
assertTrue(Arrays.asList("A", "C", "X").contains(c.getItem()));
}
}
@Test
public void testGeometricDistribution() {
ConcurrentStreamSummary<Integer> vs = new ConcurrentStreamSummary<Integer>(10);
RandomEngine re = RandomEngine.makeDefault();
for (int i = 0; i < NUM_ITERATIONS; i++) {
int z = Distributions.nextGeometric(0.25, re);
vs.offer(z);
}
List<Integer> top = vs.peek(5);
System.out.println("Geometric:");
for (Integer e : top) {
System.out.println(e);
}
int tippyTop = top.get(0);
assertEquals(0, tippyTop);
System.out.println(vs);
}
}