1 /* 2 * Copyright (C) 2009 Google Inc. 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 examples; 18 19 import com.google.caliper.BeforeExperiment; 20 import com.google.caliper.Benchmark; 21 import com.google.caliper.Param; 22 23 import java.util.AbstractList; 24 import java.util.List; 25 26 /** 27 * Measures iterating through list elements. 28 */ 29 public class ListIterationBenchmark { 30 31 @Param({"0", "10", "100", "1000"}) 32 private int length; 33 34 private List<Object> list; 35 private Object[] array; 36 setUp()37 @BeforeExperiment void setUp() { 38 array = new Object[length]; 39 for (int i = 0; i < length; i++) { 40 array[i] = new Object(); 41 } 42 43 list = new AbstractList<Object>() { 44 @Override public int size() { 45 return length; 46 } 47 48 @Override public Object get(int i) { 49 return array[i]; 50 } 51 }; 52 } 53 listIteration(int reps)54 @Benchmark int listIteration(int reps) { 55 int dummy = 0; 56 for (int i = 0; i < reps; i++) { 57 for (Object value : list) { 58 dummy |= value.hashCode(); 59 } 60 } 61 return dummy; 62 } 63 arrayIteration(int reps)64 @Benchmark int arrayIteration(int reps) { 65 int dummy = 0; 66 for (int i = 0; i < reps; i++) { 67 for (Object value : array) { 68 dummy |= value.hashCode(); 69 } 70 } 71 return dummy; 72 } 73 }