1 /*
   2  * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @summary flat-map operations
  27  * @bug 8044047 8076458
  28  */
  29 
  30 package org.openjdk.tests.java.util.stream;
  31 
  32 import org.testng.annotations.Test;
  33 
  34 import java.util.Arrays;
  35 import java.util.Collection;
  36 import java.util.concurrent.atomic.AtomicInteger;
  37 import java.util.function.Function;
  38 import java.util.function.Supplier;
  39 import java.util.stream.DoubleStream;
  40 import java.util.stream.IntStream;
  41 import java.util.stream.LongStream;
  42 import java.util.stream.OpTestCase;
  43 import java.util.stream.Stream;
  44 import java.util.stream.StreamTestDataProvider;
  45 import java.util.stream.TestData;
  46 
  47 import static java.util.stream.LambdaTestHelpers.*;
  48 import static java.util.stream.ThowableHelper.checkNPE;
  49 
  50 @Test
  51 public class FlatMapOpTest extends OpTestCase {
  52 
  53     public void testNullMapper() {
  54         checkNPE(() -> Stream.of(1).flatMap(null));
  55         checkNPE(() -> IntStream.of(1).flatMap(null));
  56         checkNPE(() -> LongStream.of(1).flatMap(null));
  57         checkNPE(() -> DoubleStream.of(1).flatMap(null));
  58     }
  59 
  60     static final Function<Integer, Stream<Integer>> integerRangeMapper
  61             = e -> IntStream.range(0, e).boxed();
  62 
  63     public void testFlatMap() {
  64         String[] stringsArray = {"hello", "there", "", "yada"};
  65         Stream<String> strings = Arrays.asList(stringsArray).stream();
  66         assertConcat(strings.flatMap(flattenChars).iterator(), "hellothereyada");
  67 
  68         assertCountSum(countTo(10).stream().flatMap(mfId), 10, 55);
  69         assertCountSum(countTo(10).stream().flatMap(mfNull), 0, 0);
  70         assertCountSum(countTo(3).stream().flatMap(mfLt), 6, 4);
  71 
  72         exerciseOps(TestData.Factory.ofArray("stringsArray", stringsArray), s -> s.flatMap(flattenChars));
  73         exerciseOps(TestData.Factory.ofArray("LONG_STRING", new String[] {LONG_STRING}), s -> s.flatMap(flattenChars));
  74     }
  75 
  76     @Test
  77     public void testClose() {
  78         AtomicInteger before = new AtomicInteger();
  79         AtomicInteger onClose = new AtomicInteger();
  80 
  81         Supplier<Stream<Integer>> s = () -> {
  82             before.set(0); onClose.set(0);
  83             return Stream.of(1, 2).peek(e -> before.getAndIncrement());
  84         };
  85 
  86         s.get().flatMap(i -> Stream.of(i, i).onClose(onClose::getAndIncrement)).count();
  87         assertEquals(before.get(), onClose.get());
  88 
  89         s.get().flatMapToInt(i -> IntStream.of(i, i).onClose(onClose::getAndIncrement)).count();
  90         assertEquals(before.get(), onClose.get());
  91 
  92         s.get().flatMapToLong(i -> LongStream.of(i, i).onClose(onClose::getAndIncrement)).count();
  93         assertEquals(before.get(), onClose.get());
  94 
  95         s.get().flatMapToDouble(i -> DoubleStream.of(i, i).onClose(onClose::getAndIncrement)).count();
  96         assertEquals(before.get(), onClose.get());
  97     }
  98 
  99     @Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
 100     public void testOps(String name, TestData.OfRef<Integer> data) {
 101         Collection<Integer> result = exerciseOps(data, s -> s.flatMap(mfId));
 102         assertEquals(data.size(), result.size());
 103 
 104         result = exerciseOps(data, s -> s.flatMap(mfNull));
 105         assertEquals(0, result.size());
 106 
 107         result = exerciseOps(data, s-> s.flatMap(e -> Stream.empty()));
 108         assertEquals(0, result.size());
 109 
 110         exerciseOps(data, s -> s.flatMap(mfLt));
 111         exerciseOps(data, s -> s.flatMap(integerRangeMapper));
 112         exerciseOps(data, s -> s.flatMap((Integer e) -> IntStream.range(0, e).boxed().limit(10)));
 113     }
 114 }