1 /* 2 * Copyright (C) 2012 The Guava Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.common.hash; 18 19 import com.google.caliper.BeforeExperiment; 20 import com.google.caliper.Benchmark; 21 import com.google.caliper.Param; 22 import com.google.common.hash.HashFunction; 23 import com.google.common.hash.Hashing; 24 25 import java.security.MessageDigest; 26 import java.security.NoSuchAlgorithmException; 27 import java.util.Random; 28 29 /** 30 * Benchmarks for comparing {@link MessageDigest}s and {@link HashFunction}s that wrap 31 * {@link MessageDigest}s. 32 * 33 * <p>Parameters for the benchmark are: 34 * <ul> 35 * <li>size: The length of the byte array to hash. 36 * <li>algorithm: the algorithm to hash with (e.g. MD5, SHA1, etc.). 37 * <li>hashMethod: how to hash the data (using the Hashing API or the MessageDigest API). 38 * </ul> 39 * 40 * @author Kurt Alfred Kluever 41 */ 42 public class MessageDigestAlgorithmBenchmark { 43 @Param({"10", "1000", "100000", "1000000"}) int size; 44 @Param Algorithm algorithm; 45 @Param HashMethod hashMethod; 46 47 private enum HashMethod { 48 MESSAGE_DIGEST_API() { 49 @Override public byte[] hash(Algorithm algorithm, byte[] input) { 50 MessageDigest md = algorithm.getMessageDigest(); 51 md.update(input); 52 return md.digest(); 53 } 54 }, 55 HASH_FUNCTION_API() { 56 @Override public byte[] hash(Algorithm algorithm, byte[] input) { 57 return algorithm.getHashFunction().hashBytes(input).asBytes(); 58 } 59 }; 60 public abstract byte[] hash(Algorithm algorithm, byte[] input); 61 } 62 63 private enum Algorithm { 64 MD5("MD5", Hashing.md5()), 65 SHA_1("SHA-1", Hashing.sha1()), 66 SHA_256("SHA-256", Hashing.sha256()), 67 SHA_512("SHA-512", Hashing.sha512()); 68 69 private final String algorithmName; 70 private final HashFunction hashFn; 71 Algorithm(String algorithmName, HashFunction hashFn) { 72 this.algorithmName = algorithmName; 73 this.hashFn = hashFn; 74 } 75 public MessageDigest getMessageDigest() { 76 try { 77 return MessageDigest.getInstance(algorithmName); 78 } catch (NoSuchAlgorithmException e) { 79 throw new AssertionError(e); 80 } 81 } 82 public HashFunction getHashFunction() { 83 return hashFn; 84 } 85 } 86 87 // Use a constant seed for all of the benchmarks to ensure apples to apples comparisons. 88 private static final int RANDOM_SEED = new Random().nextInt(); 89 90 private byte[] testBytes; 91 92 @BeforeExperiment void setUp() { 93 testBytes = new byte[size]; 94 new Random(RANDOM_SEED).nextBytes(testBytes); 95 } 96 97 @Benchmark byte hashing(int reps) { 98 byte result = 0x01; 99 HashMethod hashMethod = this.hashMethod; 100 Algorithm algorithm = this.algorithm; 101 for (int i = 0; i < reps; i++) { 102 result ^= hashMethod.hash(algorithm, testBytes)[0]; 103 } 104 return result; 105 } 106 } 107
