Murmur2HasherTest.java

/*
 * Copyright 2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License
 */
package io.atomix.catalyst.util.hash;

import org.testng.annotations.Test;

import static org.testng.Assert.assertTrue;
import static org.testng.Assert.fail;

/**
 * Murmur2 hashing algorithm test.
 *
 * @author <a href="http://github.com/kuujo>Jordan Halterman</a>
 */
@Test
public class Murmur2HasherTest {

  /**
   * Random input data with various length.
   */
  static final byte[][] input = {
    {
      (byte) 0xed, (byte) 0x53, (byte) 0xc4, (byte) 0xa5,
      (byte) 0x3b, (byte) 0x1b, (byte) 0xbd, (byte) 0xc2,
      (byte) 0x52, (byte) 0x7d, (byte) 0xc3, (byte) 0xef,
      (byte) 0x53, (byte) 0x5f, (byte) 0xae, (byte) 0x3b
    },
    {
      (byte) 0x21, (byte) 0x65, (byte) 0x59, (byte) 0x4e,
      (byte) 0xd8, (byte) 0x12, (byte) 0xf9, (byte) 0x05,
      (byte) 0x80, (byte) 0xe9, (byte) 0x1e, (byte) 0xed,
      (byte) 0xe4, (byte) 0x56, (byte) 0xbb
    },
    {
      (byte) 0x2b, (byte) 0x02, (byte) 0xb1, (byte) 0xd0,
      (byte) 0x3d, (byte) 0xce, (byte) 0x31, (byte) 0x3d,
      (byte) 0x97, (byte) 0xc4, (byte) 0x91, (byte) 0x0d,
      (byte) 0xf7, (byte) 0x17
    },
    {
      (byte) 0x8e, (byte) 0xa7, (byte) 0x9a, (byte) 0x02,
      (byte) 0xe8, (byte) 0xb9, (byte) 0x6a, (byte) 0xda,
      (byte) 0x92, (byte) 0xad, (byte) 0xe9, (byte) 0x2d,
      (byte) 0x21
    },
    {
      (byte) 0xa9, (byte) 0x6d, (byte) 0xea, (byte) 0x77,
      (byte) 0x06, (byte) 0xce, (byte) 0x1b, (byte) 0x85,
      (byte) 0x48, (byte) 0x27, (byte) 0x4c, (byte) 0xfe
    },
    {
      (byte) 0xec, (byte) 0x93, (byte) 0xa0, (byte) 0x12,
      (byte) 0x60, (byte) 0xee, (byte) 0xc8, (byte) 0x0a,
      (byte) 0xc5, (byte) 0x90, (byte) 0x62
    },
    {
      (byte) 0x55, (byte) 0x6d, (byte) 0x93, (byte) 0x66,
      (byte) 0x14, (byte) 0x6d, (byte) 0xdf, (byte) 0x00,
      (byte) 0x58, (byte) 0x99
    },
    {
      (byte) 0x3c, (byte) 0x72, (byte) 0x20, (byte) 0x1f,
      (byte) 0xd2, (byte) 0x59, (byte) 0x19, (byte) 0xdb,
      (byte) 0xa1
    },
    {
      (byte) 0x23, (byte) 0xa8, (byte) 0xb1, (byte) 0x87,
      (byte) 0x55, (byte) 0xf7, (byte) 0x8a, (byte) 0x4b,

    },
    {
      (byte) 0xe2, (byte) 0x42, (byte) 0x1c, (byte) 0x2d,
      (byte) 0xc1, (byte) 0xe4, (byte) 0x3e
    },
    {
      (byte) 0x66, (byte) 0xa6, (byte) 0xb5, (byte) 0x5a,
      (byte) 0x74, (byte) 0xd9
    },
    {
      (byte) 0xe8, (byte) 0x76, (byte) 0xa8, (byte) 0x90,
      (byte) 0x76
    },
    {
      (byte) 0xeb, (byte) 0x25, (byte) 0x3f, (byte) 0x87
    },
    {
      (byte) 0x37, (byte) 0xa0, (byte) 0xa9
    },
    {
      (byte) 0x5b, (byte) 0x5d
    },
    {
      (byte) 0x7e
    },
    {}
  };

  /**
   * Murmur 32bit hash results, special test seed.
   */
  static final int[] results32_seed = {
    0xd92e493e, 0x8b50903b, 0xc3372a7b, 0x48f07e9e,
    0x8a5e4a6e, 0x57916df4, 0xa346171f, 0x1e319c86,
    0x9e1a03cd, 0x9f973e6c, 0x2d8c77f5, 0xabed8751,
    0x296708b6, 0x24f8078b, 0x111b1553, 0xa7da1996,
    0xfe776c70};

  /**
   * Murmur 64bit hash results, special test seed.
   */
  static final long[] results64_seed = {
    0x0822b1481a92e97bl, 0xf8a9223fef0822ddl, 0x4b49e56affae3a89l,
    0xc970296e32e1d1c1l, 0xe2f9f88789f1b08fl, 0x2b0459d9b4c10c61l,
    0x377e97ea9197ee89l, 0xd2ccad460751e0e7l, 0xff162ca8d6da8c47l,
    0xf12e051405769857l, 0xdabba41293d5b035l, 0xacf326b0bb690d0el,
    0x0617f431bc1a8e04l, 0x15b81f28d576e1b2l, 0x28c1fe59e4f8e5bal,
    0x694dd315c9354ca9l, 0xa97052a8f088ae6cl
  };

  /**
   * Tests 32-bit hashes.
   */
  public void testHash32ByteArrayIntInt() {
    Hasher hasher = new Murmur2Hasher(0x71b4954d);
    for (int i = 0; i < input.length; i++) {
      int hash = hasher.hash32(input[i]);
      if (hash != results32_seed[i])
        fail(String.format("Unexpected hash32 result for example %d: 0x%08x instead of 0x%08x", i, hash, results32_seed[i]));
    }
  }

  /**
   * Tests 64-bit hashes.
   */
  public void testHash64ByteArrayIntInt() {
    Hasher hasher = new Murmur2Hasher(0x344d1f5c);
    for (int i = 0; i < input.length; i++) {
      long hash = hasher.hash64(input[i]);
      assertTrue(hash == results64_seed[i]);
    }
  }

}