diff --git a/testing-modules/streams-ordering/pom.xml b/testing-modules/streams-ordering/pom.xml new file mode 100644 index 0000000000..99d08e19be --- /dev/null +++ b/testing-modules/streams-ordering/pom.xml @@ -0,0 +1,34 @@ + + + 4.0.0 + + com.baeldung + StreamsOrdering + 1.0-SNAPSHOT + + + + junit + junit + 4.12 + test + + + + + org.openjdk.jmh + jmh-core + 1.21 + + + + org.openjdk.jmh + jmh-generator-annprocess + 1.21 + provided + + + + \ No newline at end of file diff --git a/testing-modules/streams-ordering/src/test/java/StreamsOrderingTest.java b/testing-modules/streams-ordering/src/test/java/StreamsOrderingTest.java new file mode 100644 index 0000000000..b657911780 --- /dev/null +++ b/testing-modules/streams-ordering/src/test/java/StreamsOrderingTest.java @@ -0,0 +1,148 @@ +import org.junit.Before; +import org.junit.Test; + +import java.util.*; +import java.util.function.Function; +import java.util.logging.Level; +import java.util.logging.Logger; +import java.util.stream.Collectors; +import java.util.stream.IntStream; + +import static org.junit.Assert.assertEquals; + + +public class StreamsOrderingTest { + + Logger logger = Logger.getLogger( StreamsOrderingTest.class.getName()); + + @Before + public void setUp() throws Exception { + logger.setLevel(Level.ALL); + } + + @Test + public void givenTwoCollections_whenStreamed_thenCheckOutputDifferent(){ + + List list = Arrays.asList("B", "A", "C", "D", "F"); + Set set = new TreeSet<>(Arrays.asList("B", "A", "C", "D", "F")); + + Object[] listOutput = list.stream().toArray(); + Object[] setOutput = set.stream().toArray(); + + assertEquals("[B, A, C, D, F]", Arrays.toString(listOutput)); + assertEquals("[A, B, C, D, F]", Arrays.toString(setOutput)); + + } + + @Test + public void givenTwoCollections_whenStreamedInParallel_thenCheckOutputDifferent(){ + + List list = Arrays.asList("B", "A", "C", "D", "F"); + Set set = new TreeSet<>(Arrays.asList("B", "A", "C", "D", "F")); + + Object[] listOutput = list.stream().parallel().toArray(); + Object[] setOutput = set.stream().parallel().toArray(); + + assertEquals("[B, A, C, D, F]", Arrays.toString(listOutput)); + assertEquals("[A, B, C, D, F]", Arrays.toString(setOutput)); + + } + + + + @Test + public void givenOrderedInput_whenUnorderedAndOrderedCompared_thenCheckUnorderedOutputChanges(){ + Set set = new TreeSet<>( + Arrays.asList(-9, -5, -4, -2, 1, 2, 4, 5, 7, 9, 12, 13, 16, 29, 23, 34, 57, 68, 90, 102, 230)); + + Object[] orderedArray = set.stream() + .parallel() + .limit(5) + .toArray(); + Object[] unorderedArray = set.stream() + .unordered() + .parallel() + .limit(5) + .toArray(); + + logger.info(Arrays.toString(orderedArray)); + logger.info(Arrays.toString(unorderedArray)); + } + + + @Test + public void givenUnsortedStreamInput_whenStreamSorted_thenCheckOrderChanged(){ + + List list = Arrays.asList(-3,10,-4,1,3); + + Object[] listOutput = list.stream().toArray(); + Object[] listOutputSorted = list.stream().sorted().toArray(); + + assertEquals("[-3, 10, -4, 1, 3]", Arrays.toString(listOutput)); + assertEquals("[-4, -3, 1, 3, 10]", Arrays.toString(listOutputSorted)); + + } + + @Test + public void givenUnsortedStreamInput_whenStreamDistinct_thenShowTimeTaken(){ + long start, end; + start = System.currentTimeMillis(); + IntStream.range(1,1_000_000).unordered().parallel().distinct().toArray(); + end = System.currentTimeMillis(); + System.out.println(String.format("Time taken when unordered: %d ms", (end - start))); + } + + + @Test + public void givenSameCollection_whenStreamTerminated_thenCheckEachVsEachOrdered(){ + + List list = Arrays.asList("B", "A", "C", "D", "F"); + + list.stream().parallel().forEach(e -> logger.log(Level.INFO, e)); + list.stream().parallel().forEachOrdered(e -> logger.log(Level.INFO, e)); + + } + + @Test + public void givenSameCollection_whenStreamCollected_thenCheckOutput(){ + + List list = Arrays.asList("B", "A", "C", "D", "F"); + + List collectionList = list.stream().parallel().collect(Collectors.toList()); + Set collectionSet = list.stream().parallel().collect(Collectors.toCollection(TreeSet::new)); + + assertEquals("[B, A, C, D, F]", collectionList.toString()); + assertEquals("[A, B, C, D, F]", collectionSet.toString()); + + } + + + @Test + public void givenListIterationOrder_whenStreamCollectedToMap_thenCeckOrderChanged() { + List list = Arrays.asList("A", "BB", "CCC"); + + Map hashMap = list.stream().collect(Collectors.toMap(Function.identity(), String::length)); + + Object[] keySet = hashMap.keySet().toArray(); + + assertEquals("[BB, A, CCC]", Arrays.toString(keySet)); + + } + + @Test + public void givenListIteration_whenStreamCollectedtoHashMap_thenCheckOrderMaintained() { + List list = Arrays.asList("A", "BB", "CCC", "CCC"); + + Map linkedHashMap = list.stream().collect(Collectors.toMap( + Function.identity(), + String::length, + (u, v) -> u, + LinkedHashMap::new + )); + + Object[] keySet = linkedHashMap.keySet().toArray(); + + assertEquals("[A, BB, CCC]", Arrays.toString(keySet)); + } + +} diff --git a/testing-modules/streams-ordering/src/test/java/benchmarking/TestBenchmark.java b/testing-modules/streams-ordering/src/test/java/benchmarking/TestBenchmark.java new file mode 100644 index 0000000000..a3e99e6465 --- /dev/null +++ b/testing-modules/streams-ordering/src/test/java/benchmarking/TestBenchmark.java @@ -0,0 +1,97 @@ +package benchmarking; + +import org.junit.Test; +import org.openjdk.jmh.annotations.*; +import org.openjdk.jmh.infra.Blackhole; +import org.openjdk.jmh.runner.Runner; +import org.openjdk.jmh.runner.options.Options; +import org.openjdk.jmh.runner.options.OptionsBuilder; +import org.openjdk.jmh.runner.options.TimeValue; + +import java.util.ArrayList; +import java.util.List; +import java.util.Random; +import java.util.concurrent.TimeUnit; +import java.util.stream.IntStream; + + +public class TestBenchmark +{ + + @Test + public void + launchBenchmark() throws Exception { + + Options opt = new OptionsBuilder() + // Specify which benchmarks to run. + // You can be more specific if you'd like to run only one benchmark per test. + .include(this.getClass().getName() + ".*") + // Set the following options as needed + .mode (Mode.AverageTime) + .timeUnit(TimeUnit.MICROSECONDS) + .warmupTime(TimeValue.seconds(1)) + .warmupIterations(2) + .measurementTime(TimeValue.seconds(1)) + .measurementIterations(2) + .threads(2) + .forks(1) + .shouldFailOnError(true) + .shouldDoGC(true) + //.jvmArgs("-XX:+UnlockDiagnosticVMOptions", "-XX:+PrintInlining") + //.addProfiler(WinPerfAsmProfiler.class) + .build(); + + new Runner(opt).run(); + + + } + + @Benchmark + public void givenOrderedStreamInput_whenStreamFiltered_showOpsPerMS(){ + IntStream.range(1, 100_000_000).parallel().filter(i -> i % 10 == 0).toArray(); + } + + @Benchmark + public void givenUnorderedStreamInput_whenStreamFiltered_showOpsPerMS(){ + IntStream.range(1,100_000_000).unordered().parallel().filter(i -> i % 10 == 0).toArray(); + } + + @Benchmark + public void givenUnorderedStreamInput_whenStreamDistinct_showOpsPerMS(){ + IntStream.range(1, 1_000_000).unordered().parallel().distinct().toArray(); + } + + @Benchmark + public void givenOrderedStreamInput_whenStreamDistinct_showOpsPerMS() { + //section 5.1. + IntStream.range(1, 1_000_000).parallel().distinct().toArray(); + } + + + // The JMH samples are the best documentation for how to use it + // http://hg.openjdk.java.net/code-tools/jmh/file/tip/jmh-samples/src/main/java/org/openjdk/jmh/samples/ + @State(Scope.Thread) + public static class BenchmarkState + { + List list; + + @Setup(Level.Trial) public void + initialize() { + + Random rand = new Random(); + + list = new ArrayList<>(); + for (int i = 0; i < 1000; i++) + list.add (rand.nextInt()); + } + } + + @Benchmark public void + benchmark1 (BenchmarkState state, Blackhole bh) { + + List list = state.list; + + for (int i = 0; i < 1000; i++) + bh.consume (list.get (i)); + } +} \ No newline at end of file