1 /* 2 * Copyright (C) 2013 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 com.google.caliper.runner; 18 19 import static com.google.common.base.Preconditions.checkArgument; 20 21 import com.google.caliper.Benchmark; 22 import com.google.caliper.util.Util; 23 24 import java.lang.reflect.Method; 25 import java.util.Arrays; 26 27 /** 28 * Utilities for working with methods annotated by {@link Benchmark}. 29 */ 30 final class BenchmarkMethods { 31 private static final Class<?>[] MACROBENCHMARK_PARAMS = new Class<?>[] {}; 32 private static final Class<?>[] MICROBENCHMARK_PARAMS = new Class<?>[] {int.class}; 33 private static final Class<?>[] PICOBENCHMARK_PARAMS = new Class<?>[] {long.class}; 34 35 private BenchmarkMethods() {} 36 37 enum Type { 38 MACRO, 39 MICRO, 40 PICO; 41 42 static Type of(Method benchmarkMethod) { 43 Class<?>[] parameterTypes = benchmarkMethod.getParameterTypes(); 44 if (Arrays.equals(parameterTypes, MACROBENCHMARK_PARAMS)) { 45 return MACRO; 46 } else if (Arrays.equals(parameterTypes, MICROBENCHMARK_PARAMS)) { 47 return MICRO; 48 } else if (Arrays.equals(parameterTypes, PICOBENCHMARK_PARAMS)) { 49 return PICO; 50 } else { 51 throw new IllegalArgumentException("invalid method parameters: " + benchmarkMethod); 52 } 53 } 54 } 55 56 /** 57 * Several instruments look for benchmark methods like {@code timeBlah(int reps)}; this is the 58 * centralized code that identifies such methods. 59 * 60 * <p>This method does not check the correctness of the argument types. 61 */ 62 static boolean isTimeMethod(Method method) { 63 return method.getName().startsWith("time") && Util.isPublic(method); 64 } 65 66 /** 67 * For instruments that use {@link #isTimeMethod} to identify their methods, this method checks 68 * the {@link Method} appropriately. 69 */ 70 static Method checkTimeMethod(Method timeMethod) throws InvalidBenchmarkException { 71 checkArgument(isTimeMethod(timeMethod)); 72 Class<?>[] parameterTypes = timeMethod.getParameterTypes(); 73 if (!Arrays.equals(parameterTypes, new Class<?>[] {int.class}) 74 && !Arrays.equals(parameterTypes, new Class<?>[] {long.class})) { 75 throw new InvalidBenchmarkException( 76 "Microbenchmark methods must accept a single int parameter: " + timeMethod.getName()); 77 } 78 79 // Static technically doesn't hurt anything, but it's just the completely wrong idea 80 if (Util.isStatic(timeMethod)) { 81 throw new InvalidBenchmarkException( 82 "Microbenchmark methods must not be static: " + timeMethod.getName()); 83 } 84 return timeMethod; 85 } 86 } 87
