/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements.  See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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.apache.log4j.performance;/**   Measures the time required to make a System.currentTimeMillis() and   Thread.currentThread().getName() calls.   <p>On an 233Mhz NT machine (JDK 1.1.7B) the   System.currentTimeMillis() call takes under half a microsecond to   complete whereas the Thread.currentThread().getName() call takes   about 4 micro-seconds.*/public class SystemTime {  static int RUN_LENGTH = 1000000;  static  public   void main(String[] args) {        double t = systemCurrentTimeLoop();    System.out.println("Average System.currentTimeMillis() call took " + t);    t = currentThreadNameloop();    System.out.println("Average Thread.currentThread().getName() call took " 		       + t);      }  static  double systemCurrentTimeLoop() {    long before = System.currentTimeMillis();    for(int i = 0; i < RUN_LENGTH; i++) {      System.currentTimeMillis();    }    return (System.currentTimeMillis() - before)*1000.0/RUN_LENGTH;      }  static  double currentThreadNameloop() {    long before = System.currentTimeMillis();    for(int i = 0; i < RUN_LENGTH; i++) {      Thread.currentThread().getName();    }    return (System.currentTimeMillis() - before)*1000.0/RUN_LENGTH;      }  }