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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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*/
package com.sun.max.profile;
/**
* The {@code Clock} class represents a clock source that has a continuously increasing tick
* count. A clock can be used to produce a relative timing between events by comparing the
* number of ticks between events. This can be used to implement time-based profiling
* by using a clock based on the system time.
*/
public abstract class Clock {
public abstract long getTicks();
/**
* Gets the resolution of this clock as the number of {@linkplain #getTicks() ticks} per second.
* @return the resolution of the clock
*/
public abstract long getHZ();
public static final Clock SYSTEM_NANOSECONDS = new SystemNS();
public static final Clock SYSTEM_MILLISECONDS = new SystemMS();
private static class SystemMS extends Clock {
@Override
public long getTicks() {
return System.currentTimeMillis();
}
@Override
public long getHZ() {
return 1000;
}
}
private static class SystemNS extends Clock {
@Override
public long getTicks() {
return System.nanoTime();
}
@Override
public long getHZ() {
return 1000000000;
}
}
public static int[] sampleDeltas(Clock clock, int numberOfSamples) {
final int[] result = new int[numberOfSamples];
long sample = clock.getTicks();
for (int i = 0; i < numberOfSamples; i++) {
final long newSample = clock.getTicks();
result[i] = (int) (newSample - sample);
sample = newSample;
}
return result;
}
public static void sample5(Clock clock, long[] samples) {
final long sample0 = clock.getTicks();
final long sample1 = clock.getTicks();
final long sample2 = clock.getTicks();
final long sample3 = clock.getTicks();
final long sample4 = clock.getTicks();
samples[0] = sample0;
samples[1] = sample1;
samples[2] = sample2;
samples[3] = sample3;
samples[4] = sample4;
}
}