Java tutorial
/* * Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002. * All rights reserved. Software written by Ian F. Darwin and others. * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $ * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * Java, the Duke mascot, and all variants of Sun's Java "steaming coffee * cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's, * pioneering role in inventing and promulgating (and standardizing) the Java * language and environment is gratefully acknowledged. * * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for * inventing predecessor languages C and C++ is also gratefully acknowledged. */ import java.io.BufferedOutputStream; import java.io.DataOutputStream; import java.io.FileOutputStream; import java.io.IOException; import java.text.DecimalFormat; /** * TimeComputation for processing sqrt and Input and Output operations. * * @author Ian Darwin, http://www.darwinsys.com/ * @version $Id: TimeComputation.java,v 1.7 2004/02/09 03:33:46 ian Exp $ */ public class TimeComputation { public static void main(String[] argv) { try { new TimeComputation().run(); } catch (IOException e) { System.err.println(e); } } public void run() throws IOException { DataOutputStream n = new DataOutputStream(new BufferedOutputStream(new FileOutputStream("java2s"))); long t0, t1; System.out.println("Java Starts at " + (t0 = System.currentTimeMillis())); double k; for (int i = 0; i < 100000; i++) { k = 2.1 * Math.sqrt((double) i); n.writeDouble(k); } System.out.println("Java Ends at " + (t1 = System.currentTimeMillis())); double deltaT = t1 - t0; System.out.println("This run took " + DecimalFormat.getInstance().format(deltaT / 1000.) + " seconds."); } }