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Java example source code file (HashingTest.java)
The HashingTest.java Java example source code/* * 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.base.Charsets.UTF_8; import static java.util.Arrays.asList; import com.google.common.collect.ImmutableList; import com.google.common.collect.ImmutableTable; import com.google.common.collect.Lists; import com.google.common.collect.Table.Cell; import com.google.common.primitives.Ints; import com.google.common.testing.EqualsTester; import com.google.common.testing.NullPointerTester; import com.google.common.util.concurrent.AtomicLongMap; import junit.framework.TestCase; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.nio.ByteBuffer; import java.util.Collections; import java.util.List; import java.util.Locale; import java.util.Random; /** * Unit tests for {@link Hashing}. * * @author Dimitris Andreou * @author Kurt Alfred Kluever */ public class HashingTest extends TestCase { public void testMd5() { HashTestUtils.checkAvalanche(Hashing.md5(), 100, 0.4); HashTestUtils.checkNo2BitCharacteristics(Hashing.md5()); HashTestUtils.checkNoFunnels(Hashing.md5()); HashTestUtils.assertInvariants(Hashing.md5()); assertEquals("Hashing.md5()", Hashing.md5().toString()); } public void testSha1() { HashTestUtils.checkAvalanche(Hashing.sha1(), 100, 0.4); HashTestUtils.checkNo2BitCharacteristics(Hashing.sha1()); HashTestUtils.checkNoFunnels(Hashing.sha1()); HashTestUtils.assertInvariants(Hashing.sha1()); assertEquals("Hashing.sha1()", Hashing.sha1().toString()); } public void testSha256() { HashTestUtils.checkAvalanche(Hashing.sha256(), 100, 0.4); HashTestUtils.checkNo2BitCharacteristics(Hashing.sha256()); HashTestUtils.checkNoFunnels(Hashing.sha256()); HashTestUtils.assertInvariants(Hashing.sha256()); assertEquals("Hashing.sha256()", Hashing.sha256().toString()); } public void testSha384() { HashTestUtils.checkAvalanche(Hashing.sha384(), 100, 0.4); HashTestUtils.checkNo2BitCharacteristics(Hashing.sha384()); HashTestUtils.checkNoFunnels(Hashing.sha384()); HashTestUtils.assertInvariants(Hashing.sha384()); assertEquals("Hashing.sha384()", Hashing.sha384().toString()); } public void testSha512() { HashTestUtils.checkAvalanche(Hashing.sha512(), 100, 0.4); HashTestUtils.checkNo2BitCharacteristics(Hashing.sha512()); HashTestUtils.checkNoFunnels(Hashing.sha512()); HashTestUtils.assertInvariants(Hashing.sha512()); assertEquals("Hashing.sha512()", Hashing.sha512().toString()); } public void testCrc32() { HashTestUtils.assertInvariants(Hashing.crc32()); assertEquals("Hashing.crc32()", Hashing.crc32().toString()); } public void testAdler32() { HashTestUtils.assertInvariants(Hashing.adler32()); assertEquals("Hashing.adler32()", Hashing.adler32().toString()); } public void testMurmur3_128() { HashTestUtils.check2BitAvalanche(Hashing.murmur3_128(), 250, 0.20); HashTestUtils.checkAvalanche(Hashing.murmur3_128(), 250, 0.17); HashTestUtils.checkNo2BitCharacteristics(Hashing.murmur3_128()); HashTestUtils.checkNoFunnels(Hashing.murmur3_128()); HashTestUtils.assertInvariants(Hashing.murmur3_128()); assertEquals("Hashing.murmur3_128(0)", Hashing.murmur3_128().toString()); } public void testMurmur3_32() { HashTestUtils.check2BitAvalanche(Hashing.murmur3_32(), 250, 0.20); HashTestUtils.checkAvalanche(Hashing.murmur3_32(), 250, 0.17); HashTestUtils.checkNo2BitCharacteristics(Hashing.murmur3_32()); HashTestUtils.checkNoFunnels(Hashing.murmur3_32()); HashTestUtils.assertInvariants(Hashing.murmur3_32()); assertEquals("Hashing.murmur3_32(0)", Hashing.murmur3_32().toString()); } public void testSipHash24() { HashTestUtils.check2BitAvalanche(Hashing.sipHash24(), 250, 0.14); HashTestUtils.checkAvalanche(Hashing.sipHash24(), 250, 0.10); HashTestUtils.checkNo2BitCharacteristics(Hashing.sipHash24()); HashTestUtils.checkNoFunnels(Hashing.sipHash24()); HashTestUtils.assertInvariants(Hashing.sipHash24()); assertEquals("Hashing.sipHash24(506097522914230528, 1084818905618843912)", Hashing.sipHash24().toString()); } @AndroidIncompatible // slow TODO(cpovirk): Maybe just reduce iterations under Android. public void testGoodFastHash() { for (int i = 1; i < 200; i += 17) { HashFunction hasher = Hashing.goodFastHash(i); assertTrue(hasher.bits() >= i); HashTestUtils.assertInvariants(hasher); } } // goodFastHash(32) uses Murmur3_32. Use the same epsilon bounds. public void testGoodFastHash32() { HashTestUtils.check2BitAvalanche(Hashing.goodFastHash(32), 250, 0.20); HashTestUtils.checkAvalanche(Hashing.goodFastHash(32), 250, 0.17); HashTestUtils.checkNo2BitCharacteristics(Hashing.goodFastHash(32)); HashTestUtils.checkNoFunnels(Hashing.goodFastHash(32)); HashTestUtils.assertInvariants(Hashing.goodFastHash(32)); } // goodFastHash(128) uses Murmur3_128. Use the same epsilon bounds. public void testGoodFastHash128() { HashTestUtils.check2BitAvalanche(Hashing.goodFastHash(128), 250, 0.20); HashTestUtils.checkAvalanche(Hashing.goodFastHash(128), 250, 0.17); HashTestUtils.checkNo2BitCharacteristics(Hashing.goodFastHash(128)); HashTestUtils.checkNoFunnels(Hashing.goodFastHash(128)); HashTestUtils.assertInvariants(Hashing.goodFastHash(128)); } // goodFastHash(256) uses Murmur3_128. Use the same epsilon bounds. public void testGoodFastHash256() { HashTestUtils.check2BitAvalanche(Hashing.goodFastHash(256), 250, 0.20); HashTestUtils.checkAvalanche(Hashing.goodFastHash(256), 250, 0.17); HashTestUtils.checkNo2BitCharacteristics(Hashing.goodFastHash(256)); HashTestUtils.checkNoFunnels(Hashing.goodFastHash(256)); HashTestUtils.assertInvariants(Hashing.goodFastHash(256)); } public void testConsistentHash_correctness() { long[] interestingValues = { -1, 0, 1, 2, Long.MAX_VALUE, Long.MIN_VALUE }; for (long h : interestingValues) { checkConsistentHashCorrectness(h); } Random r = new Random(7); for (int i = 0; i < 20; i++) { checkConsistentHashCorrectness(r.nextLong()); } } private void checkConsistentHashCorrectness(long hashCode) { int last = 0; for (int shards = 1; shards <= 100000; shards++) { int b = Hashing.consistentHash(hashCode, shards); if (b != last) { assertEquals(shards - 1, b); last = b; } } } public void testConsistentHash_probabilities() { AtomicLongMap<Integer> map = AtomicLongMap.create(); Random r = new Random(9); for (int i = 0; i < ITERS; i++) { countRemaps(r.nextLong(), map); } for (int shard = 2; shard <= MAX_SHARDS; shard++) { // Rough: don't exceed 1.2x the expected number of remaps by more than 20 assertTrue(map.get(shard) <= 1.2 * ITERS / shard + 20); } } private void countRemaps(long h, AtomicLongMap<Integer> map) { int last = 0; for (int shards = 2; shards <= MAX_SHARDS; shards++) { int chosen = Hashing.consistentHash(h, shards); if (chosen != last) { map.incrementAndGet(shards); last = chosen; } } } private static final int ITERS = 10000; private static final int MAX_SHARDS = 500; public void testConsistentHash_outOfRange() { try { Hashing.consistentHash(5L, 0); fail(); } catch (IllegalArgumentException expected) { } } public void testConsistentHash_ofHashCode() { checkSameResult(HashCode.fromLong(1), 1); checkSameResult(HashCode.fromLong(0x9999999999999999L), 0x9999999999999999L); checkSameResult(HashCode.fromInt(0x99999999), 0x0000000099999999L); } public void checkSameResult(HashCode hashCode, long equivLong) { assertEquals(Hashing.consistentHash(equivLong, 5555), Hashing.consistentHash(hashCode, 5555)); } /** * Check a few "golden" values to see that implementations across languages * are equivalent. */ public void testConsistentHash_linearCongruentialGeneratorCompatibility() { int[] golden100 = { 0, 55, 62, 8, 45, 59, 86, 97, 82, 59, 73, 37, 17, 56, 86, 21, 90, 37, 38, 83 }; for (int i = 0; i < golden100.length; i++) { assertEquals(golden100[i], Hashing.consistentHash(i, 100)); } assertEquals(6, Hashing.consistentHash(10863919174838991L, 11)); assertEquals(3, Hashing.consistentHash(2016238256797177309L, 11)); assertEquals(5, Hashing.consistentHash(1673758223894951030L, 11)); assertEquals(80343, Hashing.consistentHash(2, 100001)); assertEquals(22152, Hashing.consistentHash(2201, 100001)); assertEquals(15018, Hashing.consistentHash(2202, 100001)); } private static final double MAX_PERCENT_SPREAD = 0.5; private static final long RANDOM_SEED = 177L; public void testCombineOrdered_empty() { try { Hashing.combineOrdered(Collections.<HashCode>emptySet()); fail(); } catch (IllegalArgumentException expected) { } } public void testCombineOrdered_differentBitLengths() { try { HashCode unused = Hashing.combineOrdered(ImmutableList.of(HashCode.fromInt(32), HashCode.fromLong(32L))); fail(); } catch (IllegalArgumentException expected) { } } public void testCombineOrdered() { HashCode hash31 = HashCode.fromInt(31); HashCode hash32 = HashCode.fromInt(32); assertEquals(hash32, Hashing.combineOrdered(ImmutableList.of(hash32))); assertEquals(HashCode.fromBytes(new byte[] { (byte) 0x80, 0, 0, 0 }), Hashing.combineOrdered(ImmutableList.of(hash32, hash32))); assertEquals(HashCode.fromBytes(new byte[] { (byte) 0xa0, 0, 0, 0 }), Hashing.combineOrdered(ImmutableList.of(hash32, hash32, hash32))); assertFalse( Hashing.combineOrdered(ImmutableList.of(hash31, hash32)).equals( Hashing.combineOrdered(ImmutableList.of(hash32, hash31)))); } public void testCombineOrdered_randomHashCodes() { Random random = new Random(7); List<HashCode> hashCodes = Lists.newArrayList(); for (int i = 0; i < 10; i++) { hashCodes.add(HashCode.fromLong(random.nextLong())); } HashCode hashCode1 = Hashing.combineOrdered(hashCodes); Collections.shuffle(hashCodes, random); HashCode hashCode2 = Hashing.combineOrdered(hashCodes); assertFalse(hashCode1.equals(hashCode2)); } public void testCombineUnordered_empty() { try { Hashing.combineUnordered(Collections.<HashCode>emptySet()); fail(); } catch (IllegalArgumentException expected) { } } public void testCombineUnordered_differentBitLengths() { try { HashCode unused = Hashing.combineUnordered(ImmutableList.of(HashCode.fromInt(32), HashCode.fromLong(32L))); fail(); } catch (IllegalArgumentException expected) { } } public void testCombineUnordered() { HashCode hash31 = HashCode.fromInt(31); HashCode hash32 = HashCode.fromInt(32); assertEquals(hash32, Hashing.combineUnordered(ImmutableList.of(hash32))); assertEquals(HashCode.fromInt(64), Hashing.combineUnordered(ImmutableList.of(hash32, hash32))); assertEquals(HashCode.fromInt(96), Hashing.combineUnordered(ImmutableList.of(hash32, hash32, hash32))); assertEquals( Hashing.combineUnordered(ImmutableList.of(hash31, hash32)), Hashing.combineUnordered(ImmutableList.of(hash32, hash31))); } public void testCombineUnordered_randomHashCodes() { Random random = new Random(RANDOM_SEED); List<HashCode> hashCodes = Lists.newArrayList(); for (int i = 0; i < 10; i++) { hashCodes.add(HashCode.fromLong(random.nextLong())); } HashCode hashCode1 = Hashing.combineUnordered(hashCodes); Collections.shuffle(hashCodes); HashCode hashCode2 = Hashing.combineUnordered(hashCodes); assertEquals(hashCode1, hashCode2); } // This isn't specified by contract, but it'll still be nice to know if this behavior changes. public void testConcatenating_equals() { new EqualsTester() .addEqualityGroup(Hashing.concatenating(asList(Hashing.md5()))) .addEqualityGroup(Hashing.concatenating(asList(Hashing.murmur3_32()))) .addEqualityGroup( Hashing.concatenating(Hashing.md5(), Hashing.md5()), Hashing.concatenating(asList(Hashing.md5(), Hashing.md5()))) .addEqualityGroup( Hashing.concatenating(Hashing.murmur3_32(), Hashing.md5()), Hashing.concatenating(asList(Hashing.murmur3_32(), Hashing.md5()))) .addEqualityGroup( Hashing.concatenating(Hashing.md5(), Hashing.murmur3_32()), Hashing.concatenating(asList(Hashing.md5(), Hashing.murmur3_32()))) .testEquals(); } public void testConcatenatingIterable_bits() { assertEquals( Hashing.md5().bits() + Hashing.md5().bits(), Hashing.concatenating(asList(Hashing.md5(), Hashing.md5())).bits()); assertEquals( Hashing.md5().bits() + Hashing.murmur3_32().bits(), Hashing.concatenating(asList(Hashing.md5(), Hashing.murmur3_32())).bits()); assertEquals( Hashing.md5().bits() + Hashing.murmur3_32().bits() + Hashing.murmur3_128().bits(), Hashing.concatenating( asList(Hashing.md5(), Hashing.murmur3_32(), Hashing.murmur3_128())).bits()); } public void testConcatenatingVarArgs_bits() { assertEquals( Hashing.md5().bits() + Hashing.md5().bits(), Hashing.concatenating(Hashing.md5(), Hashing.md5()).bits()); assertEquals( Hashing.md5().bits() + Hashing.murmur3_32().bits(), Hashing.concatenating(Hashing.md5(), Hashing.murmur3_32()).bits()); assertEquals( Hashing.md5().bits() + Hashing.murmur3_32().bits() + Hashing.murmur3_128().bits(), Hashing.concatenating(Hashing.md5(), Hashing.murmur3_32(), Hashing.murmur3_128()).bits()); } public void testConcatenatingHashFunction_makeHash() { byte[] md5Hash = Hashing.md5().hashLong(42L).asBytes(); byte[] murmur3Hash = Hashing.murmur3_32().hashLong(42L).asBytes(); byte[] combined = new byte[md5Hash.length + murmur3Hash.length]; ByteBuffer buffer = ByteBuffer.wrap(combined); buffer.put(md5Hash); buffer.put(murmur3Hash); HashCode expected = HashCode.fromBytes(combined); assertEquals(expected, Hashing.concatenating(Hashing.md5(), Hashing.murmur3_32()).hashLong(42L)); assertEquals(expected, Hashing.concatenating(asList(Hashing.md5(), Hashing.murmur3_32())).hashLong(42L)); } public void testHashIntReverseBytesVsHashBytesIntsToByteArray() { int input = 42; assertEquals( Hashing.md5().hashBytes(Ints.toByteArray(input)), Hashing.md5().hashInt(Integer.reverseBytes(input))); } public void testHashIntVsForLoop() { int input = 42; HashCode expected = Hashing.md5().hashInt(input); Hasher hasher = Hashing.md5().newHasher(); for (int i = 0; i < 32; i += 8) { hasher.putByte((byte) (input >> i)); } HashCode actual = hasher.hash(); assertEquals(expected, actual); } private static final String EMPTY_STRING = ""; private static final String TQBFJOTLD = "The quick brown fox jumps over the lazy dog"; private static final String TQBFJOTLDP = "The quick brown fox jumps over the lazy dog."; private static final ImmutableTable<HashFunction, String, String> KNOWN_HASHES = ImmutableTable.<HashFunction, String, String>builder() .put(Hashing.adler32(), EMPTY_STRING, "01000000") .put(Hashing.adler32(), TQBFJOTLD, "da0fdc5b") .put(Hashing.adler32(), TQBFJOTLDP, "0810e46b") .put(Hashing.md5(), EMPTY_STRING, "d41d8cd98f00b204e9800998ecf8427e") .put(Hashing.md5(), TQBFJOTLD, "9e107d9d372bb6826bd81d3542a419d6") .put(Hashing.md5(), TQBFJOTLDP, "e4d909c290d0fb1ca068ffaddf22cbd0") .put(Hashing.murmur3_128(), EMPTY_STRING, "00000000000000000000000000000000") .put(Hashing.murmur3_128(), TQBFJOTLD, "6c1b07bc7bbc4be347939ac4a93c437a") .put(Hashing.murmur3_128(), TQBFJOTLDP, "c902e99e1f4899cde7b68789a3a15d69") .put(Hashing.murmur3_32(), EMPTY_STRING, "00000000") .put(Hashing.murmur3_32(), TQBFJOTLD, "23f74f2e") .put(Hashing.murmur3_32(), TQBFJOTLDP, "fc8bc4d5") .put(Hashing.sha1(), EMPTY_STRING, "da39a3ee5e6b4b0d3255bfef95601890afd80709") .put(Hashing.sha1(), TQBFJOTLD, "2fd4e1c67a2d28fced849ee1bb76e7391b93eb12") .put(Hashing.sha1(), TQBFJOTLDP, "408d94384216f890ff7a0c3528e8bed1e0b01621") .put( Hashing.sha256(), EMPTY_STRING, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855") .put( Hashing.sha256(), TQBFJOTLD, "d7a8fbb307d7809469ca9abcb0082e4f8d5651e46d3cdb762d02d0bf37c9e592") .put( Hashing.sha256(), TQBFJOTLDP, "ef537f25c895bfa782526529a9b63d97aa631564d5d789c2b765448c8635fb6c") .put( Hashing.sha384(), EMPTY_STRING, "38b060a751ac96384cd9327eb1b1e36a21fdb71114be07434c0cc7bf63f6e1da2" + "74edebfe76f65fbd51ad2f14898b95b") .put( Hashing.sha384(), TQBFJOTLD, "ca737f1014a48f4c0b6dd43cb177b0afd9e5169367544c494011e3317dbf9a509" + "cb1e5dc1e85a941bbee3d7f2afbc9b1") .put( Hashing.sha384(), TQBFJOTLDP, "ed892481d8272ca6df370bf706e4d7bc1b5739fa2177aae6c50e946678718fc67" + "a7af2819a021c2fc34e91bdb63409d7") .put( Hashing.sha512(), EMPTY_STRING, "cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce" + "47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e") .put( Hashing.sha512(), TQBFJOTLD, "07e547d9586f6a73f73fbac0435ed76951218fb7d0c8d788a309d785436bbb64" + "2e93a252a954f23912547d1e8a3b5ed6e1bfd7097821233fa0538f3db854fee6") .put( Hashing.sha512(), TQBFJOTLDP, "91ea1245f20d46ae9a037a989f54f1f790f0a47607eeb8a14d12890cea77a1bb" + "c6c7ed9cf205e67b7f2b8fd4c7dfd3a7a8617e45f3c463d481c7e586c39ac1ed") .put(Hashing.crc32(), EMPTY_STRING, "00000000") .put(Hashing.crc32(), TQBFJOTLD, "39a34f41") .put(Hashing.crc32(), TQBFJOTLDP, "e9259051") .put(Hashing.sipHash24(), EMPTY_STRING, "310e0edd47db6f72") .put(Hashing.sipHash24(), TQBFJOTLD, "e46f1fdc05612752") .put(Hashing.sipHash24(), TQBFJOTLDP, "9b602581fce4d4f8") .put(Hashing.crc32c(), EMPTY_STRING, "00000000") .put(Hashing.crc32c(), TQBFJOTLD, "04046222") .put(Hashing.crc32c(), TQBFJOTLDP, "b3970019") .put(Hashing.farmHashFingerprint64(), EMPTY_STRING, "4f40902f3b6ae19a") .put(Hashing.farmHashFingerprint64(), TQBFJOTLD, "34511b3bf383beab") .put(Hashing.farmHashFingerprint64(), TQBFJOTLDP, "737d7e5f8660653e") .build(); public void testAllHashFunctionsHaveKnownHashes() throws Exception { for (Method method : Hashing.class.getDeclaredMethods()) { if (method.getReturnType().equals(HashFunction.class) // must return HashFunction && Modifier.isPublic(method.getModifiers()) // only the public methods && method.getParameterTypes().length == 0) { // only the seed-less grapes^W hash functions HashFunction hashFunction = (HashFunction) method.invoke(Hashing.class); assertTrue("There should be at least 3 entries in KNOWN_HASHES for " + hashFunction, KNOWN_HASHES.row(hashFunction).size() >= 3); } } } public void testKnownUtf8Hashing() { for (Cell<HashFunction, String, String> cell : KNOWN_HASHES.cellSet()) { HashFunction func = cell.getRowKey(); String input = cell.getColumnKey(); String expected = cell.getValue(); assertEquals( String.format(Locale.ROOT, "Known hash for hash(%s, UTF_8) failed", input), expected, func.hashString(input, UTF_8).toString()); } } public void testNullPointers() { NullPointerTester tester = new NullPointerTester() .setDefault(byte[].class, "secret key".getBytes(UTF_8)) .setDefault(HashCode.class, HashCode.fromLong(0)); tester.testAllPublicStaticMethods(Hashing.class); } public void testSeedlessHashFunctionEquals() throws Exception { assertSeedlessHashFunctionEquals(Hashing.class); } public void testSeededHashFunctionEquals() throws Exception { assertSeededHashFunctionEquals(Hashing.class); } /** * Tests equality of {@link Hashing#goodFastHash} instances. This test must be separate from * {@link #testSeededHashFunctionEquals} because the parameter to {@code goodFastHash} is a size, * not a seed, and because that size is rounded up. Thus, {@code goodFastHash} instances with * different parameters can be equal. That fact is a problem for {@code * testSeededHashFunctionEquals}. */ public void testGoodFastHashEquals() throws Exception { HashFunction hashFunction1a = Hashing.goodFastHash(1); HashFunction hashFunction1b = Hashing.goodFastHash(32); HashFunction hashFunction2a = Hashing.goodFastHash(33); HashFunction hashFunction2b = Hashing.goodFastHash(128); HashFunction hashFunction3a = Hashing.goodFastHash(129); HashFunction hashFunction3b = Hashing.goodFastHash(256); HashFunction hashFunction4a = Hashing.goodFastHash(257); HashFunction hashFunction4b = Hashing.goodFastHash(384); new EqualsTester() .addEqualityGroup(hashFunction1a, hashFunction1b) .addEqualityGroup(hashFunction2a, hashFunction2b) .addEqualityGroup(hashFunction3a, hashFunction3b) .addEqualityGroup(hashFunction4a, hashFunction4b) .testEquals(); assertEquals(hashFunction1a.toString(), hashFunction1b.toString()); assertEquals(hashFunction2a.toString(), hashFunction2b.toString()); assertEquals(hashFunction3a.toString(), hashFunction3b.toString()); assertEquals(hashFunction4a.toString(), hashFunction4b.toString()); } static void assertSeedlessHashFunctionEquals(Class<?> clazz) throws Exception { for (Method method : clazz.getDeclaredMethods()) { if (method.getReturnType().equals(HashFunction.class) // must return HashFunction && Modifier.isPublic(method.getModifiers()) // only the public methods && method.getParameterTypes().length == 0) { // only the seed-less hash functions HashFunction hashFunction1a = (HashFunction) method.invoke(clazz); HashFunction hashFunction1b = (HashFunction) method.invoke(clazz); new EqualsTester() .addEqualityGroup(hashFunction1a, hashFunction1b) .testEquals(); // Make sure we're returning not only equal instances, but constants. assertSame(hashFunction1a, hashFunction1b); assertEquals(hashFunction1a.toString(), hashFunction1b.toString()); } } } static void assertSeededHashFunctionEquals(Class<?> clazz) throws Exception { Random random = new Random(RANDOM_SEED); for (Method method : clazz.getDeclaredMethods()) { if (method.getReturnType().equals(HashFunction.class) // must return HashFunction && Modifier.isPublic(method.getModifiers()) // only the public methods && method.getParameterTypes().length != 0 // only the seeded hash functions && !method.getName().equals("concatenating") // don't test Hashing.concatenating() && !method.getName().equals("goodFastHash") // tested in testGoodFastHashEquals && !method.getName().startsWith("hmac")) { // skip hmac functions Object[] params1 = new Object[method.getParameterTypes().length]; Object[] params2 = new Object[method.getParameterTypes().length]; for (int i = 0; i < params1.length; i++) { if (method.getParameterTypes()[i] == int.class) { params1[i] = random.nextInt(); params2[i] = random.nextInt(); } else if (method.getParameterTypes()[i] == long.class) { params1[i] = random.nextLong(); params2[i] = random.nextLong(); } else { fail("Unable to create a random parameter for " + method.getParameterTypes()[i]); } } HashFunction hashFunction1a = (HashFunction) method.invoke(clazz, params1); HashFunction hashFunction1b = (HashFunction) method.invoke(clazz, params1); HashFunction hashFunction2 = (HashFunction) method.invoke(clazz, params2); new EqualsTester() .addEqualityGroup(hashFunction1a, hashFunction1b) .addEqualityGroup(hashFunction2) .testEquals(); assertEquals(hashFunction1a.toString(), hashFunction1b.toString()); } } } } Other Java examples (source code examples)Here is a short list of links related to this Java HashingTest.java source code file: |
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