1 /* 2 * Copyright (C) 2010 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 benchmarks; 18 19 /** 20 * How do various ways of iterating through an array compare? 21 */ 22 public class ArrayIterationBenchmark { 23 Foo[] mArray = new Foo[27]; 24 { 25 for (int i = 0; i < mArray.length; ++i) mArray[i] = new Foo(); 26 } 27 public void timeArrayIteration(int reps) { 28 for (int rep = 0; rep < reps; ++rep) { 29 int sum = 0; 30 for (int i = 0; i < mArray.length; i++) { 31 sum += mArray[i].mSplat; 32 } 33 } 34 } 35 public void timeArrayIterationCached(int reps) { 36 for (int rep = 0; rep < reps; ++rep) { 37 int sum = 0; 38 Foo[] localArray = mArray; 39 int len = localArray.length; 40 41 for (int i = 0; i < len; i++) { 42 sum += localArray[i].mSplat; 43 } 44 } 45 } 46 public void timeArrayIterationForEach(int reps) { 47 for (int rep = 0; rep < reps; ++rep) { 48 int sum = 0; 49 for (Foo a: mArray) { 50 sum += a.mSplat; 51 } 52 } 53 } 54 } 55
