Example usage for java.util.stream Stream generate

Introduction

In this page you can find the example usage for java.util.stream Stream generate.

Prototype

public static <T> Stream<T> generate(Supplier<? extends T> s) 

Source Link

Document

Returns an infinite sequential unordered stream where each element is generated by the provided Supplier .

Usage

From source file:Main.java

public static void main(String[] args) {
    Stream.generate(Math::random).limit(5).forEach(System.out::println);

}

---

From source file:Main.java

public static void main(String[] args) {
    Stream.generate(new Random()::nextInt).limit(5).forEach(System.out::println);
}

---

From source file:Main.java

public static void main(String[] args) {
    Stream.generate(new Random()::nextDouble).limit(10).forEach(System.out::println);

}

---

From source file:com.ikanow.aleph2.enrichment.utils.services.JsScriptEngineTestService.java

/** Entry point
 * @param args//  w  w w . j  a v a  2  s  . c o m
 * @throws IOException 
 */
public static void main(String[] args) throws IOException {
    if (args.length < 3) {
        System.out
                .println("ARGS: <script-file> <input-file> <output-prefix> [{[len: <LEN>], [group: <GROUP>]}]");
    }

    // STEP 1: load script file

    final String user_script = Files.toString(new File(args[0]), Charsets.UTF_8);

    // STEP 2: get a stream for the JSON file

    final InputStream io_stream = new FileInputStream(new File(args[1]));

    // STEP 3: set up control if applicable

    Optional<JsonNode> json = Optional.of("").filter(__ -> args.length > 3).map(__ -> args[3])
            .map(Lambdas.wrap_u(j -> _mapper.readTree(j)));

    // STEP 4: set up the various objects

    final DataBucketBean bucket = Mockito.mock(DataBucketBean.class);

    final JsScriptEngineService service_under_test = new JsScriptEngineService();

    final LinkedList<ObjectNode> emitted = new LinkedList<>();
    final LinkedList<JsonNode> grouped = new LinkedList<>();
    final LinkedList<JsonNode> externally_emitted = new LinkedList<>();

    final IEnrichmentModuleContext context = Mockito.mock(IEnrichmentModuleContext.class, new Answer<Void>() {
        @SuppressWarnings("unchecked")
        public Void answer(InvocationOnMock invocation) {
            try {
                Object[] args = invocation.getArguments();
                if (invocation.getMethod().getName().equals("emitMutableObject")) {
                    final Optional<JsonNode> grouping = (Optional<JsonNode>) args[3];
                    if (grouping.isPresent()) {
                        grouped.add(grouping.get());
                    }
                    emitted.add((ObjectNode) args[1]);
                } else if (invocation.getMethod().getName().equals("externalEmit")) {
                    final DataBucketBean to = (DataBucketBean) args[0];
                    final Either<JsonNode, Map<String, Object>> out = (Either<JsonNode, Map<String, Object>>) args[1];
                    externally_emitted
                            .add(((ObjectNode) out.left().value()).put("__a2_bucket", to.full_name()));
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }
    });

    final EnrichmentControlMetadataBean control = BeanTemplateUtils.build(EnrichmentControlMetadataBean.class)
            .with(EnrichmentControlMetadataBean::config,
                    new LinkedHashMap<String, Object>(
                            ImmutableMap.<String, Object>builder().put("script", user_script).build()))
            .done().get();

    service_under_test.onStageInitialize(context, bucket, control,
            Tuples._2T(ProcessingStage.batch, ProcessingStage.grouping), Optional.empty());

    final BeJsonParser json_parser = new BeJsonParser();

    // Run the file through

    final Stream<Tuple2<Long, IBatchRecord>> json_stream = StreamUtils
            .takeUntil(Stream.generate(() -> json_parser.getNextRecord(io_stream)), i -> null == i)
            .map(j -> Tuples._2T(0L, new BatchRecord(j)));

    service_under_test.onObjectBatch(json_stream, json.map(j -> j.get("len")).map(j -> (int) j.asLong(0L)),
            json.map(j -> j.get("group")));

    System.out.println("RESULTS: ");
    System.out.println("emitted: " + emitted.size());
    System.out.println("grouped: " + grouped.size());
    System.out.println("externally emitted: " + externally_emitted.size());
    Files.write(emitted.stream().map(j -> j.toString()).collect(Collectors.joining(";")),
            new File(args[2] + "emit.json"), Charsets.UTF_8);
    Files.write(grouped.stream().map(j -> j.toString()).collect(Collectors.joining(";")),
            new File(args[2] + "group.json"), Charsets.UTF_8);
    Files.write(externally_emitted.stream().map(j -> j.toString()).collect(Collectors.joining(";")),
            new File(args[2] + "external_emit.json"), Charsets.UTF_8);
}

---

From source file:alfio.controller.support.TemplateProcessorTest.java

@Test
public void resultingImageMustBeUnder300x150() {
    Stream.generate(
            () -> Pair.of(String.valueOf(random.nextInt(10_000)), String.valueOf(random.nextInt(100_000))))
            .limit(1000).forEach(this::assertDimensionsUnder300x150);
}

---

From source file:com.watchrabbit.crawler.executor.strategy.PageContentWordsStrategy.java

@Override
public List<String> generateKeywords(CrawlForm form, RemoteWebDriver driver) {
    String pageText = driver.findElement(By.tagName("body")).getText();
    List<String> words = Stream.of(pageText.split("\\s"))
            .map(wordWithPunctation -> wordWithPunctation.replaceAll("[^a-zA-Z]", ""))
            .map(mixCaseWord -> mixCaseWord.toLowerCase())
            .filter(anyWord -> anyWord.length() > 3 && anyWord.length() < 20).collect(toList());

    Random random = new Random();
    return Stream.generate(() -> random.nextInt() % words.size())
            .map(index -> index < 0 ? index + words.size() : index).map(index -> words.get(index)).distinct()
            .limit(maximumKeywords).collect(toList());
}

---

From source file:com.nirmata.workflow.details.TestJsonSerializer.java

@Test
public void testRunnableTask() {
    Map<TaskId, ExecutableTask> tasks = Stream.generate(() -> "").limit(random.nextInt(3) + 1)
            .collect(Collectors.toMap(s -> new TaskId(), s -> new ExecutableTask(new RunId(), new TaskId(),
                    randomTaskType(), randomMap(), random.nextBoolean())));
    List<RunnableTaskDag> taskDags = Stream.generate(() -> new RunnableTaskDag(new TaskId(), randomTasks()))
            .limit(random.nextInt(3) + 1).collect(Collectors.toList());
    LocalDateTime completionTime = random.nextBoolean() ? LocalDateTime.now() : null;
    RunId parentRunId = random.nextBoolean() ? new RunId() : null;
    RunnableTask runnableTask = new RunnableTask(tasks, taskDags, LocalDateTime.now(), completionTime,
            parentRunId);//  ww w  .j  a  v a 2 s . c  om
    JsonNode node = newRunnableTask(runnableTask);
    String str = nodeToString(node);
    System.out.println(str);

    RunnableTask unRunnableTask = getRunnableTask(fromString(str));
    Assert.assertEquals(runnableTask, unRunnableTask);
}

---

From source file:alfio.util.EventUtil.java

public static Stream<MapSqlParameterSource> generateStreamForTicketCreation(int limit) {
    return Stream.generate(MapSqlParameterSource::new).limit(limit);
}

---

From source file:com.cloudbees.jenkins.support.filter.FilteredOutputStreamTest.java

@Test
public void shouldSupportMultipleUsesWithReset() throws IOException {
    FilteredOutputStream out = new FilteredOutputStream(testOutput, s -> s);
    List<String> paragraphs = Stream.generate(() -> FAKE_TEXT).limit(10).collect(Collectors.toList());
    StringBuilder b = new StringBuilder();
    for (String paragraph : paragraphs) {
        out.write(paragraph.getBytes(UTF_8));
        out.write('\n');
        b.append(paragraph).append('\n');
        out.reset();/*www .java2 s.  c om*/
    }
    String expected = b.toString();
    assertThat(new String(testOutput.toByteArray(), UTF_8)).isNotEmpty().isEqualTo(expected);
}

---

From source file:com.nirmata.workflow.details.TestJsonSerializer.java

private Map<String, String> randomMap() {
    return Stream.generate(random::nextInt).limit(random.nextInt(3) + 1)
            .collect(Collectors.toMap(n -> Integer.toString(n * 4), n -> Integer.toString(n * 2)));
}

---

• «
• 1
• 2
• »