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 17package benchmarks; 18 19import java.util.HashMap; 20import java.util.Hashtable; 21import java.util.LinkedHashMap; 22import java.util.concurrent.ConcurrentHashMap; 23 24/** 25 * How do the various hash maps compare? 26 */ 27public class HashedCollectionsBenchmark { 28 public void timeHashMapGet(int reps) { 29 HashMap<String, String> map = new HashMap<String, String>(); 30 map.put("hello", "world"); 31 for (int i = 0; i < reps; ++i) { 32 map.get("hello"); 33 } 34 } 35 public void timeHashMapGet_Synchronized(int reps) { 36 HashMap<String, String> map = new HashMap<String, String>(); 37 synchronized (map) { 38 map.put("hello", "world"); 39 } 40 for (int i = 0; i < reps; ++i) { 41 synchronized (map) { 42 map.get("hello"); 43 } 44 } 45 } 46 public void timeHashtableGet(int reps) { 47 Hashtable<String, String> map = new Hashtable<String, String>(); 48 map.put("hello", "world"); 49 for (int i = 0; i < reps; ++i) { 50 map.get("hello"); 51 } 52 } 53 public void timeLinkedHashMapGet(int reps) { 54 LinkedHashMap<String, String> map = new LinkedHashMap<String, String>(); 55 map.put("hello", "world"); 56 for (int i = 0; i < reps; ++i) { 57 map.get("hello"); 58 } 59 } 60 public void timeConcurrentHashMapGet(int reps) { 61 ConcurrentHashMap<String, String> map = new ConcurrentHashMap<String, String>(); 62 map.put("hello", "world"); 63 for (int i = 0; i < reps; ++i) { 64 map.get("hello"); 65 } 66 } 67} 68