test/tck/SystemTest.java

/*
 * Written by members of JCP JSR-166 Expert Group and released to the
 * public domain. Use, modify, and redistribute this code in any way
 * without acknowledgement. Other contributors include Andrew Wright,
 * Jeffrey Hayes, Pat Fischer, Mike Judd.
 */

import junit.framework.*;

public class SystemTest extends JSR166TestCase {
    public static void main(String[] args) {
        junit.textui.TestRunner.run(suite());   
    }
    
    public static Test suite() {
        return new TestSuite(SystemTest.class);
    }

    /**
     * Nanos between readings of millis is no longer than millis.
     * This shows only that nano timing not (much) worse than milli.
     */
    public void testNanoTime1() {
        try {
            long m1 = System.currentTimeMillis();
            Thread.sleep(1);
            long n1 = System.nanoTime();
            Thread.sleep(SHORT_DELAY_MS);
            long n2 = System.nanoTime();
            Thread.sleep(1);
            long m2 = System.currentTimeMillis();
            long millis = m2 - m1;
            long nanos = n2 - n1;
            
            assertTrue(nanos >= 0);
            assertTrue(nanos <= millis * 1000000);
        }
        catch(InterruptedException ie) {
            fail("unexpected exception");
        }
    }

    /**
     * Millis between readings of nanos is no longer than nanos
     * This shows only that nano timing not (much) worse than milli.
     */
    public void testNanoTime2() {
        try {
            long n1 = System.nanoTime();
            Thread.sleep(1);
            long m1 = System.currentTimeMillis();
            Thread.sleep(SHORT_DELAY_MS);
            long m2 = System.currentTimeMillis();
            Thread.sleep(1);
            long n2 = System.nanoTime();
            long millis = m2 - m1;
            long nanos = n2 - n1;
            
            assertTrue(nanos >= 0);
            assertTrue(millis * 1000000 <= nanos);
        }
        catch(InterruptedException ie) {
            fail("unexpected exception");
        }
    }

}

Revision:	1.2
Committed:	Sun Sep 14 20:42:41 2003 UTC (20 years, 7 months ago) by dl
Branch:	MAIN
Changes since 1.1:	+43 -46 lines
Log Message:	New base class JSR166TestCase
#	User	Rev	Content
1	dl	1.1	/*
2			* Written by members of JCP JSR-166 Expert Group and released to the
3			* public domain. Use, modify, and redistribute this code in any way
4			* without acknowledgement. Other contributors include Andrew Wright,
5			* Jeffrey Hayes, Pat Fischer, Mike Judd.
6			*/
7
8			import junit.framework.*;
9
10	dl	1.2	public class SystemTest extends JSR166TestCase {
11	dl	1.1	public static void main(String[] args) {
12			junit.textui.TestRunner.run(suite());
13			}
14
15			public static Test suite() {
16			return new TestSuite(SystemTest.class);
17			}
18
19	dl	1.2	/**
20			* Nanos between readings of millis is no longer than millis.
21			* This shows only that nano timing not (much) worse than milli.
22			*/
23	dl	1.1	public void testNanoTime1() {
24	dl	1.2	try {
25			long m1 = System.currentTimeMillis();
26			Thread.sleep(1);
27			long n1 = System.nanoTime();
28			Thread.sleep(SHORT_DELAY_MS);
29			long n2 = System.nanoTime();
30			Thread.sleep(1);
31			long m2 = System.currentTimeMillis();
32			long millis = m2 - m1;
33			long nanos = n2 - n1;
34
35			assertTrue(nanos >= 0);
36			assertTrue(nanos <= millis * 1000000);
37			}
38			catch(InterruptedException ie) {
39			fail("unexpected exception");
40			}
41	dl	1.1	}
42
43	dl	1.2	/**
44			* Millis between readings of nanos is no longer than nanos
45			* This shows only that nano timing not (much) worse than milli.
46			*/
47	dl	1.1	public void testNanoTime2() {
48	dl	1.2	try {
49			long n1 = System.nanoTime();
50			Thread.sleep(1);
51			long m1 = System.currentTimeMillis();
52			Thread.sleep(SHORT_DELAY_MS);
53			long m2 = System.currentTimeMillis();
54			Thread.sleep(1);
55			long n2 = System.nanoTime();
56			long millis = m2 - m1;
57			long nanos = n2 - n1;
58
59			assertTrue(nanos >= 0);
60			assertTrue(millis * 1000000 <= nanos);
61			}
62			catch(InterruptedException ie) {
63			fail("unexpected exception");
64			}
65	dl	1.1	}
66
67			}
68