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      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.common.base.Ascii;
     23 import com.google.common.collect.Lists;
     24 import com.google.common.primitives.Chars;
     25 
     26 import java.util.Collections;
     27 import java.util.List;
     28 import java.util.Locale;
     29 import java.util.Random;
     30 
     31 /**
     32  * Benchmarks for the ASCII class.
     33  *
     34  * @author Kevin Bourrillion
     35  */
     36 public class AsciiBenchmark {
     37   private static String ALPHA =
     38       "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
     39   private static String NONALPHA =
     40       "0123456789`~-_=+[]{}|;:',.<>/?!@#$%^&*()\"\\";
     41 
     42   @Param({"20", "2000"}) int size;
     43   @Param({"2", "20"}) int nonAlphaRatio; // one non-alpha char per this many chars
     44   @Param boolean noWorkToDo;
     45 
     46   Random random;
     47   String testString;
     48 
     49   @BeforeExperiment void setUp() {
     50     random = new Random();
     51 
     52     int nonAlpha = size / nonAlphaRatio;
     53     int alpha = size - nonAlpha;
     54 
     55     List<Character> chars = Lists.newArrayListWithCapacity(size);
     56     for (int i = 0; i < alpha; i++) {
     57       chars.add(randomAlpha());
     58     }
     59     for (int i = 0; i < nonAlpha; i++) {
     60       chars.add(randomNonAlpha());
     61     }
     62     Collections.shuffle(chars, random);
     63     char[] array = Chars.toArray(chars);
     64     this.testString = new String(array);
     65   }
     66 
     67   private char randomAlpha() {
     68     return ALPHA.charAt(random.nextInt(ALPHA.length()));
     69   }
     70 
     71   private char randomNonAlpha() {
     72     return NONALPHA.charAt(random.nextInt(NONALPHA.length()));
     73   }
     74 
     75   @Benchmark int asciiStringToUpperCase(int reps) {
     76     String string = noWorkToDo
     77         ? Ascii.toUpperCase(testString)
     78         : testString;
     79 
     80     int dummy = 0;
     81     for (int i = 0; i < reps; i++) {
     82       dummy += Ascii.toUpperCase(string).length();
     83     }
     84     return dummy;
     85   }
     86 
     87   @Benchmark int asciiCharSequenceToUpperCase(int reps) {
     88     String string = noWorkToDo
     89         ? charSequenceToUpperCase(testString)
     90         : testString;
     91 
     92     int dummy = 0;
     93     for (int i = 0; i < reps; i++) {
     94       dummy += charSequenceToUpperCase(string).length();
     95     }
     96     return dummy;
     97   }
     98 
     99   @Benchmark int stringToUpperCase(int reps) {
    100     String string = noWorkToDo
    101         ? testString.toUpperCase(Locale.US)
    102         : testString;
    103 
    104     int dummy = 0;
    105     for (int i = 0; i < reps; i++) {
    106       dummy += string.toUpperCase(Locale.US).length();
    107     }
    108     return dummy;
    109   }
    110 
    111   @Benchmark boolean equalsIgnoreCaseCharSequence(int reps) {
    112     // This benchmark has no concept of "noWorkToDo".
    113     String upperString = testString.toUpperCase();
    114     CharSequence testSeq = new StringBuilder(testString);
    115     CharSequence upperSeq = new StringBuilder(upperString);
    116     CharSequence[] lhs = new CharSequence[] { testString, testSeq, testString, testSeq };
    117     CharSequence[] rhs = new CharSequence[] { upperString, upperString, upperSeq, upperSeq };
    118 
    119     boolean dummy = false;
    120     for (int i = 0; i < reps; i++) {
    121       dummy ^= Ascii.equalsIgnoreCase(lhs[i & 0x3], rhs[i & 0x3]);
    122     }
    123     return dummy;
    124   }
    125 
    126   @Benchmark boolean equalsIgnoreCaseStringOnly(int reps) {
    127     // This benchmark has no concept of "noWorkToDo".
    128     String lhs = testString;
    129     String rhs = testString.toUpperCase();
    130 
    131     boolean dummy = false;
    132     for (int i = 0; i < reps; i++) {
    133       dummy ^= Ascii.equalsIgnoreCase(lhs, rhs);
    134     }
    135     return dummy;
    136   }
    137 
    138   @Benchmark boolean equalsIgnoreCaseJDK(int reps) {
    139     // This benchmark has no concept of "noWorkToDo".
    140     String lhs = testString;
    141     String rhs = testString.toUpperCase();
    142 
    143     boolean dummy = false;
    144     for (int i = 0; i < reps; i++) {
    145         dummy ^= lhs.equalsIgnoreCase(rhs);
    146     }
    147     return dummy;
    148   }
    149 
    150   @Benchmark boolean isUpperCase(int reps) {
    151     // This benchmark has no concept of "noWorkToDo".
    152     char[] chars = testString.toCharArray();
    153 
    154     boolean dummy = false;
    155     for (int i = 0; i < reps; i++) {
    156       for (int n = 0; n < chars.length; n++) {
    157         dummy ^= Ascii.isUpperCase(chars[n]);
    158       }
    159     }
    160     return dummy;
    161   }
    162 
    163   static String charSequenceToUpperCase(CharSequence chars) {
    164     int length = chars.length();
    165     StringBuilder builder = new StringBuilder(length);
    166     for (int i = 0; i < length; i++) {
    167       builder.append(Ascii.toUpperCase(chars.charAt(i)));
    168     }
    169     return builder.toString();
    170   }
    171 }
    172