/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program 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 for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Oct 26, 2006
*/
package com.bigdata.util;
import junit.framework.TestCase;
/**
* Test suite for {@link NanosecondTimestampFactory}.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public class TestNanosecondTimestampFactory extends TestCase {
public TestNanosecondTimestampFactory() {
}
public TestNanosecondTimestampFactory(String arg0) {
super(arg0);
}
/**
* Test determines whether nano times are always distinct from the last
* generated nanos time (as assigned by {@link System#nanoTime()}.
* <p>
* Note: This test is NOT designed to pass/fail but simply to test determine
* a characteristic of the platform on which it is executing.
*/
public void test_nextNanoTime() {
final int limit = 1000000;
long lastNanoTime = System.nanoTime();
long nanoTime;
long minDiff = Long.MAX_VALUE;
for( int i=0; i<limit; i++ ) {
nanoTime = System.nanoTime();
if (nanoTime == lastNanoTime) {
System.err
.println("This platform can generate identical timestamps with nanosecond resolution");
return;
}
long diff = nanoTime - lastNanoTime;
if( diff < 0 ) diff = -diff;
if( diff < minDiff ) minDiff = diff;
lastNanoTime = nanoTime;
}
System.err.println("Nano times appear to be distinct on this platorm.");
System.err.println("Minimum difference in nanos is " + minDiff
+ " over " + limit + " trials");
}
/**
* Test verifies that nano times are always distinct from the last generated
* nanos time (as assigned by {@link NanosecondTimestampFactory#nextNanoTime()}.
*/
public void test_nextNanoTime2() {
final int limit = 1000000;
long lastNanoTime = System.nanoTime() - 1;
long nanoTime;
long minDiff = Long.MAX_VALUE;
for( int i=0; i<limit; i++ ) {
nanoTime = NanosecondTimestampFactory.nextNanoTime();
if( nanoTime == lastNanoTime ) fail("Same nano time?");
long diff = nanoTime - lastNanoTime;
if( diff < 0 ) diff = -diff;
if( diff < minDiff ) minDiff = diff;
lastNanoTime = nanoTime;
}
System.err.println("Minimum difference in nanos is " + minDiff
+ " over " + limit + " trials");
}
}