Example usage for java.util.stream IntStream range

Introduction

In this page you can find the example usage for java.util.stream IntStream range.

Prototype

public static IntStream range(int startInclusive, int endExclusive)

Source Link

Document

Returns a sequential ordered IntStream from startInclusive (inclusive) to endExclusive (exclusive) by an incremental step of 1 .

Usage

From source file:Main.java

private static boolean isPrime(int number) {
    IntPredicate isDivisible = index -> number % index == 0;
    return number > 1 && IntStream.range(2, number - 1).noneMatch(isDivisible);
}

From source file:Main.java

public static <T> Stream<List<T>> batches(List<T> source, int length) {
    if (length <= 0)
        throw new IllegalArgumentException("length = " + length);
    int size = source.size();
    if (size <= 0)
        return Stream.empty();
    int fullChunks = (size - 1) / length;
    return IntStream.range(0, fullChunks + 1)
            .mapToObj(n -> source.subList(n * length, n == fullChunks ? size : (n + 1) * length));
}

From source file:io.moquette.spi.impl.DebugUtils.java

public static IntStream intStream(byte[] array) {
    return IntStream.range(0, array.length).map(idx -> array[idx]);
}

From source file:br.ufpr.inf.gres.utils.TestCaseUtils.java

/**
 * Get the test cases selected indexes in relation the test case set
 *
 * @param testCasesSelected The test cases that I want discovery the indexes
 * @param testCases The test cases set//from  w  w  w . j  a va 2s. com
 * @return
 * @throws TestCaseSetSelectionException
 */
public static List<Integer> getVariables(List<String> testCasesSelected, List<TestCase> testCases)
        throws TestCaseSetSelectionException {

    return Arrays.asList(ArrayUtils.toObject(IntStream.range(0, testCases.size())
            .filter(i -> testCasesSelected.contains(testCases.get(i).getDescription())).toArray()));
}

From source file:org.kie.server.services.prometheus.PrometheusMetrics.java

private static double[] rangeNano(int start, int end) {
    return IntStream.range(start, end).mapToDouble(l -> toNano((long) l)).toArray();
}

From source file:org.kie.server.services.prometheus.PrometheusMetrics.java

private static double[] rangeMicro(int start, int end) {
    return IntStream.range(start, end).mapToDouble(l -> toMicro((long) l)).toArray();
}

From source file:com.simiacryptus.mindseye.test.PCAUtil.java

/**
 * Forked from Apache Commons Math//  w w w  .j  av a 2  s  .c  o m
 *
 * @param stream the stream
 * @return covariance covariance
 */
@Nonnull
public static RealMatrix getCovariance(@Nonnull final Supplier<Stream<double[]>> stream) {
    final int dimension = stream.get().findAny().get().length;
    final List<DoubleStatistics> statList = IntStream.range(0, dimension * dimension)
            .mapToObj(i -> new DoubleStatistics()).collect(Collectors.toList());
    stream.get().forEach(array -> {
        for (int i = 0; i < dimension; i++) {
            for (int j = 0; j <= i; j++) {
                statList.get(i * dimension + j).accept(array[i] * array[j]);
            }
        }
        RecycleBin.DOUBLES.recycle(array, array.length);
    });
    @Nonnull
    final RealMatrix covariance = new BlockRealMatrix(dimension, dimension);
    for (int i = 0; i < dimension; i++) {
        for (int j = 0; j <= i; j++) {
            final double v = statList.get(i + dimension * j).getAverage();
            covariance.setEntry(i, j, v);
            covariance.setEntry(j, i, v);
        }
    }
    return covariance;
}

From source file:notaql.engines.json.datamodel.ValueConverter.java

public static Value convertToNotaQL(Object o) {
    // Atom values
    if (o == null)
        return new NullValue();
    if (o.equals(JSONObject.NULL))
        return new NullValue();
    if (o instanceof String)
        return new StringValue((String) o);
    if (o instanceof Number)
        return new NumberValue((Number) o);
    if (o instanceof Boolean)
        return new BooleanValue((Boolean) o);

    // complex values
    if (o instanceof JSONArray) {
        final JSONArray array = (JSONArray) o;
        final ListValue result = new ListValue();
        IntStream.range(0, array.length()).forEach(i -> result.add(convertToNotaQL(array.get(i))));
        return result;
    }/*ww w  . ja v  a 2 s .  c o m*/

    if (o instanceof JSONObject) {
        final JSONObject jsonObject = (JSONObject) o;
        final ObjectValue result = new ObjectValue();

        final Iterator<String> keyIterator = jsonObject.keys();
        while (keyIterator.hasNext()) {
            final String key = keyIterator.next();
            final Step<String> step = new Step<>(key);
            final Value value = convertToNotaQL(jsonObject.get(key));

            result.put(step, value);
        }
        return result;
    }

    throw new EvaluationException("Unsupported type read: " + o.getClass() + ": " + o.toString());
}

From source file:org.apache.samza.sql.testutil.ReflectionUtils.java

/**
 * Create an instance of the specified class with constuctor
 * matching the argument array.//www .  j a  v a 2  s .com
 * @param clazz name of the class
 * @param args argument array
 * @param <T> type fo the class
 * @return instance of the class, or null if anything went wrong
 */
@SuppressWarnings("unchecked")
public static <T> T createInstance(String clazz, Object... args) {
    Validate.notNull(clazz, "null class name");
    try {
        Class<T> classObj = (Class<T>) Class.forName(clazz);
        Class<?>[] argTypes = new Class<?>[args.length];
        IntStream.range(0, args.length).forEach(i -> argTypes[i] = args[i].getClass());
        Constructor<T> ctor = classObj.getDeclaredConstructor(argTypes);
        return ctor.newInstance(args);
    } catch (Exception e) {
        LOG.warn("Failed to create instance for: " + clazz, e);
        return null;
    }
}

From source file:org.apache.bookkeeper.tools.framework.CommandUtils.java

private static void printIndent(PrintStream printer, int indent) {
    IntStream.range(0, indent).forEach(ignored -> printer.print(" "));
}