/*
* Copyright (C) 2011 The Guava 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 com.google.common.hash;
import static com.google.common.hash.Hashing.murmur3_128;
import com.google.common.base.Charsets;
import com.google.common.hash.HashTestUtils.HashFn;
import junit.framework.TestCase;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
/**
* Tests for {@link Murmur3_128HashFunction}.
*/
public class Murmur3Hash128Test extends TestCase {
public void testKnownValues() {
assertHash(0, 0x629942693e10f867L, 0x92db0b82baeb5347L, "hell");
assertHash(1, 0xa78ddff5adae8d10L, 0x128900ef20900135L, "hello");
assertHash(2, 0x8a486b23f422e826L, 0xf962a2c58947765fL, "hello ");
assertHash(3, 0x2ea59f466f6bed8cL, 0xc610990acc428a17L, "hello w");
assertHash(4, 0x79f6305a386c572cL, 0x46305aed3483b94eL, "hello wo");
assertHash(5, 0xc2219d213ec1f1b5L, 0xa1d8e2e0a52785bdL, "hello wor");
assertHash(0, 0xe34bbc7bbc071b6cL, 0x7a433ca9c49a9347L,
"The quick brown fox jumps over the lazy dog");
assertHash(0, 0x658ca970ff85269aL, 0x43fee3eaa68e5c3eL,
"The quick brown fox jumps over the lazy cog");
// Known output from Python smhasher
HashCode foxHash =
murmur3_128(0).hashString("The quick brown fox jumps over the lazy dog", Charsets.UTF_8);
assertEquals("6c1b07bc7bbc4be347939ac4a93c437a", foxHash.toString());
}
private static void assertHash(int seed, long expected1, long expected2, String stringInput) {
HashCode expected = toHashCode(expected1, expected2);
byte[] input = HashTestUtils.ascii(stringInput);
assertEquals(expected, murmur3_128(seed).hashBytes(input));
assertEquals(expected, murmur3_128(seed).newHasher().putBytes(input).hash());
}
/**
* Returns a {@link HashCode} for a sequence of longs, in big-endian order.
*/
private static HashCode toHashCode(long... longs) {
ByteBuffer bb = ByteBuffer.wrap(new byte[longs.length * 8]).order(ByteOrder.LITTLE_ENDIAN);
for (long x : longs) {
bb.putLong(x);
}
return HashCode.fromBytes(bb.array());
}
public void testParanoid() {
HashFn hf = new HashFn() {
@Override public byte[] hash(byte[] input, int seed) {
Hasher hasher = murmur3_128(seed).newHasher();
Funnels.byteArrayFunnel().funnel(input, hasher);
return hasher.hash().asBytes();
}
};
// Murmur3F, MurmurHash3 for x64, 128-bit (MurmurHash3_x64_128)
// From http://code.google.com/p/smhasher/source/browse/trunk/main.cpp
HashTestUtils.verifyHashFunction(hf, 128, 0x6384BA69);
}
public void testInvariants() {
HashTestUtils.assertInvariants(murmur3_128());
}
}