1 /* 2 * Copyright (C) 2010 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.base; 18 19 import com.google.caliper.BeforeExperiment; 20 import com.google.caliper.Benchmark; 21 import com.google.caliper.Param; 22 import com.google.caliper.runner.CaliperMain; 23 import com.google.common.base.CharMatcher.FastMatcher; 24 25 import java.util.BitSet; 26 import java.util.Random; 27 28 /** 29 * Benchmark for the {@link CharMatcher#WHITESPACE} implementation. 30 */ 31 public class WhitespaceMatcherBenchmark { 32 private static final int STRING_LENGTH = 10000; 33 34 private static final String OLD_WHITESPACE_TABLE = 35 "\u0001\u0000\u00a0\u0000\u0000\u0000\u0000\u0000" 36 + "\u0000\u0009\n\u000b\u000c\r\u0000\u0000\u2028\u2029\u0000\u0000\u0000\u0000\u0000\u202f" 37 + "\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0020\u0000\u0000\u0000\u0000\u0000" 38 + "\u0000\u0000\u0000\u0000\u0000\u3000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000" 39 + "\u0000\u0000\u0085\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a" 40 + "\u0000\u0000\u0000\u0000\u0000\u205f\u1680\u0000\u0000\u180e\u0000\u0000\u0000"; 41 42 public static final CharMatcher OLD_WHITESPACE = new FastMatcher("CharMatcher.WHITESPACE") { 43 @Override public boolean matches(char c) { 44 return OLD_WHITESPACE_TABLE.charAt(c % 79) == c; 45 } 46 }; 47 48 @Param 49 private boolean useNew; 50 51 @Param({"20", "50", "80"}) 52 private int percentMatching; 53 54 private String teststring; 55 private CharMatcher matcher; 56 main(String[] args)57 public static void main(String[] args) throws Exception { 58 CaliperMain.main(WhitespaceMatcherBenchmark.class, new String[] {}); 59 } 60 61 @BeforeExperiment setUp()62 protected void setUp() { 63 BitSet bitSet = new BitSet(); 64 for (int i = 0; i < OLD_WHITESPACE_TABLE.length(); i++) { 65 bitSet.set(OLD_WHITESPACE_TABLE.charAt(i)); 66 } 67 bitSet.clear(0); 68 bitSet.clear(1); 69 matcher = useNew ? CharMatcher.WHITESPACE : OLD_WHITESPACE; 70 teststring = newTestString(new Random(1), bitSet, percentMatching); 71 } 72 countIn(int reps)73 @Benchmark public int countIn(int reps) { 74 int result = 0; 75 CharMatcher matcher = this.matcher; 76 String teststring = this.teststring; 77 for (int i = 0; i < reps; i++) { 78 result += matcher.countIn(teststring); 79 } 80 return result; 81 } 82 collapseFrom(int reps)83 @Benchmark public int collapseFrom(int reps) { 84 int result = 0; 85 CharMatcher matcher = this.matcher; 86 String teststring = this.teststring; 87 for (int i = 0; i < reps; i++) { 88 result += System.identityHashCode(matcher.collapseFrom(teststring, ' ')); 89 } 90 return result; 91 } 92 allMatchingChars(BitSet bitSet)93 private static String allMatchingChars(BitSet bitSet) { 94 final char[] result = new char[bitSet.cardinality()]; 95 for (int j = 0, c = bitSet.nextSetBit(0); j < result.length; ++j) { 96 result[j] = (char) c; 97 c = bitSet.nextSetBit(c + 1); 98 } 99 return new String(result); 100 } 101 newTestString(Random random, BitSet bitSet, int percentMatching)102 private static String newTestString(Random random, BitSet bitSet, int percentMatching) { 103 final String allMatchingChars = allMatchingChars(bitSet); 104 final char[] result = new char[STRING_LENGTH]; 105 // Fill with matching chars. 106 for (int i = 0; i < result.length; i++) { 107 result[i] = allMatchingChars.charAt(random.nextInt(allMatchingChars.length())); 108 } 109 // Replace some of chars by non-matching. 110 int remaining = (int) ((100 - percentMatching) * result.length / 100.0 + 0.5); 111 while (remaining > 0) { 112 final char c = (char) random.nextInt(); 113 if (bitSet.get(c)) { 114 final int pos = random.nextInt(result.length); 115 if (bitSet.get(result[pos])) { 116 result[pos] = c; 117 remaining--; 118 } 119 } 120 } 121 return new String(result); 122 } 123 } 124