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 {
MESSAGE_DIGEST_API()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     },
HASH_FUNCTION_API()55     HASH_FUNCTION_API() {
56       @Override public byte[] hash(Algorithm algorithm, byte[] input) {
57         return algorithm.getHashFunction().hashBytes(input).asBytes();
58       }
59     };
hash(Algorithm algorithm, byte[] input)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;
Algorithm(String algorithmName, HashFunction hashFn)71     Algorithm(String algorithmName, HashFunction hashFn) {
72       this.algorithmName = algorithmName;
73       this.hashFn = hashFn;
74     }
getMessageDigest()75     public MessageDigest getMessageDigest() {
76       try {
77         return MessageDigest.getInstance(algorithmName);
78       } catch (NoSuchAlgorithmException e) {
79         throw new AssertionError(e);
80       }
81     }
getHashFunction()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 
setUp()92   @BeforeExperiment void setUp() {
93     testBytes = new byte[size];
94     new Random(RANDOM_SEED).nextBytes(testBytes);
95   }
96 
hashing(int reps)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