/*
* Copyright 2015, 2016 Tagir Valeev
*
* 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 one.util.streamex;
import static org.junit.Assert.*;
import java.util.Map;
import java.util.OptionalDouble;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import one.util.streamex.DoubleCollector;
import one.util.streamex.DoubleStreamEx;
import one.util.streamex.IntStreamEx;
import one.util.streamex.LongCollector;
import one.util.streamex.LongStreamEx;
import org.junit.FixMethodOrder;
import org.junit.Test;
import org.junit.runners.MethodSorters;
/**
* @author Tagir Valeev
*/
@FixMethodOrder(MethodSorters.NAME_ASCENDING)
public class DoubleCollectorTest {
@Test
public void testJoining() {
String expected = IntStream.range(0, 10000).asDoubleStream().mapToObj(String::valueOf).collect(
Collectors.joining(", "));
assertEquals(expected, IntStreamEx.range(10000).asDoubleStream().collect(DoubleCollector.joining(", ")));
assertEquals(expected, IntStreamEx.range(10000).asDoubleStream().parallel().collect(
DoubleCollector.joining(", ")));
String expected2 = IntStreamEx.range(0, 1000).asDoubleStream().boxed().toList().toString();
assertEquals(expected2, IntStreamEx.range(1000).asDoubleStream().collect(
DoubleCollector.joining(", ", "[", "]")));
assertEquals(expected2, IntStreamEx.range(1000).asDoubleStream().parallel().collect(
DoubleCollector.joining(", ", "[", "]")));
}
@Test
public void testCounting() {
assertEquals(5000L, (long) IntStreamEx.range(10000).asDoubleStream().atLeast(5000).collect(
DoubleCollector.counting()));
assertEquals(5000L, (long) IntStreamEx.range(10000).asDoubleStream().parallel().atLeast(5000).collect(
DoubleCollector.counting()));
assertEquals(5000, (int) IntStreamEx.range(10000).asDoubleStream().atLeast(5000).collect(
DoubleCollector.countingInt()));
assertEquals(5000, (int) IntStreamEx.range(10000).asDoubleStream().parallel().atLeast(5000).collect(
DoubleCollector.countingInt()));
}
@Test
public void testSumming() {
assertEquals(3725, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(DoubleCollector.summing()), 0.0);
assertEquals(3725, IntStreamEx.range(100).asDoubleStream().parallel().atLeast(50).collect(
DoubleCollector.summing()), 0.0);
}
@Test
public void testMin() {
assertEquals(50, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(DoubleCollector.min())
.getAsDouble(), 0.0);
assertEquals(50, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(
DoubleCollector.min().andThen(OptionalDouble::getAsDouble)), 0.0);
assertFalse(IntStreamEx.range(100).asDoubleStream().atLeast(200).collect(DoubleCollector.min()).isPresent());
}
@Test
public void testMax() {
assertEquals(99, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(DoubleCollector.max())
.getAsDouble(), 0.0);
assertEquals(99, IntStreamEx.range(100).asDoubleStream().parallel().atLeast(50).collect(DoubleCollector.max())
.getAsDouble(), 0.0);
assertFalse(IntStreamEx.range(100).asDoubleStream().atLeast(200).collect(DoubleCollector.max()).isPresent());
}
@Test
public void testToArray() {
assertArrayEquals(new double[] { 0, 1, 2, 3, 4 }, IntStreamEx.of(0, 1, 2, 3, 4).asDoubleStream().collect(
DoubleCollector.toArray()), 0.0);
assertArrayEquals(IntStreamEx.range(1000).asDoubleStream().toFloatArray(), IntStreamEx.range(1000).parallel()
.asDoubleStream().collect(DoubleCollector.toFloatArray()), 0.0f);
}
@Test
public void testPartitioning() {
double[] expectedEven = IntStream.range(0, 1000).asDoubleStream().map(i -> i * 2).toArray();
double[] expectedOdd = IntStream.range(0, 1000).asDoubleStream().map(i -> i * 2 + 1).toArray();
Map<Boolean, double[]> oddEven = IntStreamEx.range(2000).asDoubleStream().collect(
DoubleCollector.partitioningBy(i -> i % 2 == 0));
assertArrayEquals(expectedEven, oddEven.get(true), 0.0);
assertArrayEquals(expectedOdd, oddEven.get(false), 0.0);
oddEven = IntStreamEx.range(2000).asDoubleStream().parallel().collect(
DoubleCollector.partitioningBy(i -> i % 2 == 0));
assertArrayEquals(expectedEven, oddEven.get(true), 0.0);
assertArrayEquals(expectedOdd, oddEven.get(false), 0.0);
}
@Test
public void testGroupingBy() {
Map<Double, double[]> collected = IntStreamEx.range(2000).asDoubleStream().collect(
DoubleCollector.groupingBy(i -> i % 3));
for (double i = 0; i < 3; i++) {
double rem = i;
assertArrayEquals(IntStream.range(0, 2000).asDoubleStream().filter(a -> a % 3 == rem).toArray(), collected
.get(i), 0.0);
}
collected = IntStreamEx.range(2000).asDoubleStream().parallel().collect(DoubleCollector.groupingBy(i -> i % 3));
for (double i = 0; i < 3; i++) {
double rem = i;
assertArrayEquals(IntStream.range(0, 2000).asDoubleStream().filter(a -> a % 3 == rem).toArray(), collected
.get(i), 0.0);
}
}
@Test
public void testAsCollector() {
assertEquals(499.5, IntStream.range(0, 1000).asDoubleStream().boxed().collect(DoubleCollector.summarizing())
.getAverage(), 0.000001);
assertEquals(499.5, IntStream.range(0, 1000).parallel().asDoubleStream().boxed().collect(
DoubleCollector.summarizing()).getAverage(), 0.000001);
}
@Test
public void testAdaptor() {
assertEquals(499.5, IntStreamEx.range(1000).asDoubleStream().collect(
DoubleCollector.of(DoubleCollector.summarizing())).getAverage(), 0.000001);
assertEquals(499.5, IntStreamEx.range(1000).parallel().asDoubleStream().collect(
DoubleCollector.of(Collectors.summarizingDouble(Double::doubleValue))).getAverage(), 0.000001);
}
@Test
public void testReducing() {
assertEquals(7.0, DoubleStreamEx.of(1.0, 2.0, 3.5).collect(DoubleCollector.reducing(1.0, (a, b) -> a * b)), 0.0);
assertEquals(7.0, DoubleStreamEx.of(1.0, 2.0, 3.5).parallel().collect(
DoubleCollector.reducing(1.0, (a, b) -> a * b)), 0.0);
}
@Test
public void testMapping() {
assertEquals(10100.0, IntStreamEx.rangeClosed(0, 100).asDoubleStream().collect(
DoubleCollector.mapping(x -> x * 2, DoubleCollector.summing())), 0.0);
assertArrayEquals(LongStreamEx.of(1, 1, 2, 3).toArray(), DoubleStreamEx.of(0.8, 1.3, 1.7, 2.9).collect(
DoubleCollector.mappingToObj(Math::round, LongCollector.toArray())));
}
@Test
public void testAveraging() {
assertFalse(DoubleStreamEx.empty().collect(DoubleCollector.averaging()).isPresent());
assertEquals(1.0,
DoubleStreamEx.of(0.0, 0.5, 1.0, 1.5, 2.0).collect(DoubleCollector.averaging()).getAsDouble(), 0.0);
}
@Test
public void testToBooleanArray() {
assertArrayEquals(new boolean[0], DoubleStreamEx.empty().collect(DoubleCollector.toBooleanArray(x -> true)));
boolean[] expected = new boolean[] { true, false, false, true };
assertArrayEquals(expected, DoubleStreamEx.of(1.0, 1.5, 2.7, 3.0).collect(
DoubleCollector.toBooleanArray(x -> Math.floor(x) == x)));
assertArrayEquals(expected, DoubleStreamEx.of(1.0, 1.5, 2.7, 3.0).parallel().collect(
DoubleCollector.toBooleanArray(x -> Math.floor(x) == x)));
}
}