Examples with Memory org.apache.datasketches.memory.Memory used on opensource projects

Example 66 with Memory

use of org.apache.datasketches.memory.Memory in project sketches-core by DataSketches.

the class MurmurHash3 method hash.

// --Hash of ByteBuffer---------------------------------------------------
/**
 * Hash the remaining bytes of the given ByteBuffer starting at position().
 *
 * @param buf The input ByteBuffer. It must be non-null and non-empty.
 * @param seed A long valued seed.
 * @return a 128-bit hash of the input as a long array of size 2.
 */
public static long[] hash(final ByteBuffer buf, final long seed) {
    Objects.requireNonNull(buf);
    final int pos = buf.position();
    final int rem = buf.remaining();
    checkPositive(rem);
    final Memory mem = Memory.wrap(buf, ByteOrder.LITTLE_ENDIAN).region(pos, rem);
    return hash(mem, seed);
}

Example 67 with Memory

use of org.apache.datasketches.memory.Memory in project sketches-core by DataSketches.

the class ReservoirItemsSketchTest method checkBadMemory.

@Test(expectedExceptions = SketchesArgumentException.class)
public void checkBadMemory() {
    byte[] bytes = new byte[4];
    Memory mem = Memory.wrap(bytes);
    try {
        PreambleUtil.getAndCheckPreLongs(mem);
        fail();
    } catch (final SketchesArgumentException e) {
    // expected
    }
    bytes = new byte[8];
    // only 1 preLong worth of items in bytearray
    bytes[0] = 2;
    mem = Memory.wrap(bytes);
    PreambleUtil.getAndCheckPreLongs(mem);
}

Example 68 with Memory

use of org.apache.datasketches.memory.Memory in project sketches-core by DataSketches.

the class ReservoirItemsSketchTest method checkEmptySketch.

@Test
public void checkEmptySketch() {
    final ReservoirItemsSketch<String> ris = ReservoirItemsSketch.newInstance(5);
    assertTrue(ris.getSamples() == null);
    final byte[] sketchBytes = ris.toByteArray(new ArrayOfStringsSerDe());
    final Memory mem = Memory.wrap(sketchBytes);
    // only minPreLongs bytes and should deserialize to empty
    assertEquals(sketchBytes.length, Family.RESERVOIR.getMinPreLongs() << 3);
    final ArrayOfStringsSerDe serDe = new ArrayOfStringsSerDe();
    final ReservoirItemsSketch<String> loadedRis = ReservoirItemsSketch.heapify(mem, serDe);
    assertEquals(loadedRis.getNumSamples(), 0);
    println("Empty sketch:");
    println("  Preamble:");
    println(PreambleUtil.preambleToString(mem));
    println("  Sketch:");
    println(ris.toString());
}

Example 69 with Memory

use of org.apache.datasketches.memory.Memory in project sketches-core by DataSketches.

the class DoublesUnionBuilderTest method checkBuilds.

@Test
public void checkBuilds() {
    UpdateDoublesSketch qs1 = DoublesSketch.builder().build();
    for (int i = 0; i < 1000; i++) {
        qs1.update(i);
    }
    int bytes = qs1.getCompactStorageBytes();
    WritableMemory dstMem = WritableMemory.writableWrap(new byte[bytes]);
    qs1.putMemory(dstMem);
    Memory srcMem = dstMem;
    DoublesUnionBuilder bldr = new DoublesUnionBuilder();
    bldr.setMaxK(128);
    // virgin union
    DoublesUnion union = bldr.build();
    union = DoublesUnion.heapify(srcMem);
    DoublesSketch qs2 = union.getResult();
    assertEquals(qs1.getCompactStorageBytes(), qs2.getCompactStorageBytes());
    union = DoublesUnion.heapify(qs2);
    DoublesSketch qs3 = union.getResult();
    assertEquals(qs2.getCompactStorageBytes(), qs3.getCompactStorageBytes());
    assertFalse(qs2 == qs3);
}

Example 70 with Memory

use of org.apache.datasketches.memory.Memory in project sketches-core by DataSketches.

the class DoublesUtilTest method checkPrintMemData2.

@Test
public void checkPrintMemData2() {
    final int k = PreambleUtil.DEFAULT_K;
    final int n = 0;
    final DoublesSketch qs = buildAndLoadQS(k, n);
    final byte[] byteArr = qs.toByteArray();
    final Memory mem = Memory.wrap(byteArr);
    println(DoublesUtil.memToString(true, true, mem));
}