예제 #1
0
  public void testAltIndexIsReversible() throws Exception {
    final long max = Long.MAX_VALUE - 1L; // must be even!
    final long incr = 1000000L;
    final Random random = new Random(1L);
    final byte[] fingerprint = new byte[1];

    for (long index = 0; index != next(index, incr, max); index = next(index, incr, max)) {
      random.nextBytes(fingerprint);
      int f = (random.nextInt(126) + 1) * (random.nextBoolean() ? 1 : -1);
      final long altIndex = MURMUR128_BEALDUPRAS_32.altIndex(index, f, max);
      final long altAltIndex = MURMUR128_BEALDUPRAS_32.altIndex(altIndex, f, max);
      assertEquals("index should equal altIndex(altIndex(index)):" + f, index, altAltIndex);
    }
  }
예제 #2
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  public void testIndexIsModuloM() throws Exception {
    final int min = Integer.MIN_VALUE;
    final int max = Integer.MAX_VALUE;
    final int incr = 100000;
    final long m = 0x1DEAL;

    for (int hash = min; hash != next(hash, incr, max); hash = next(hash, incr, max)) {
      final long index = MURMUR128_BEALDUPRAS_32.index(hash, m);
      assertThat(index).isLessThan(m);
      assertThat(index).isGreaterThan(-1L);
    }
  }
예제 #3
0
 public void testFingerprintBoundaries() throws Exception {
   assertThat(MURMUR128_BEALDUPRAS_32.fingerprint(0x80000000, 1)).isEqualTo(0x01);
   assertThat(MURMUR128_BEALDUPRAS_32.fingerprint(0xC0000000, 2)).isEqualTo(0x03);
   assertThat(MURMUR128_BEALDUPRAS_32.fingerprint(0xE0000000, 3)).isEqualTo(0x04);
   assertThat(MURMUR128_BEALDUPRAS_32.fingerprint(0xE0000000, 8)).isEqualTo(0xE0);
   assertThat(MURMUR128_BEALDUPRAS_32.fingerprint(0xE0000000, 16)).isEqualTo(0xE000);
   assertThat(MURMUR128_BEALDUPRAS_32.fingerprint(0x80000000, Integer.SIZE)).isEqualTo(0x80000000);
   for (int f = 1; f < Integer.SIZE; f++) {
     assertThat(MURMUR128_BEALDUPRAS_32.fingerprint(0x00, f)).isNotEqualTo(0x00);
   }
 }