/* * Copyright 2012-2015 org.opencloudb. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.opencloudb.util; import java.util.HashMap; import java.util.Map; /** * @author mycat */ public class HashMapMain { public void t() { String[] keys = new String[] { "a", "b", "c", "d", "e" }; long t = System.currentTimeMillis(); int count = 1000000; Map<String, String> m = new HashMap<String, String>(); t = System.currentTimeMillis(); for (int i = 0; i < count; i++) { for (String key : keys) { m.put(key, "String.value"); } for (String key : keys) { m.remove(key); } } System.out.println((System.currentTimeMillis() - t) * 1000 * 1000 / (count * keys.length * 2) + " ns"); } }