/* * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ import sun.misc.SystemRandom; import sun.misc.SystemRandomImpl; import java.util.Arrays; /* * @test * @summary Test for sun.misc.SystemRandom */ public class SystemRandomTest { public static void main(String[] args) { byte[] bytes = new byte[8]; System.out.println("SystemRandomTest... (" + bytes.length + " bytes / invocation)"); long t0 = System.nanoTime(); SystemRandom.getInstance().getBytes(bytes); long t1 = System.nanoTime(); System.out.println("1st invocation: " + (t1 - t0) + " ns, result: " + Arrays.toString(bytes)); final int N = 1_000_000; t0 = System.nanoTime(); for (int i = 0; i < N; i++) { SystemRandom.getInstance().getBytes(bytes); } t1 = System.nanoTime(); System.out.println("Following " + N + " invocations: " + ((double) (t1 - t0) / 1e9d) + " s, (" + ((t1 - t0) / N) + " ns/invocation)"); } }