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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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).
 *
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 * 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 org.graalvm.compiler.debug;

import java.lang.management.ThreadMXBean;

A consistent source of timing data that should be used by all facilities in the debug package.
/**
 * A consistent source of timing data that should be used by all facilities in the debug package.
 */
public class TimeSource {
    private static final boolean USING_BEAN;
    private static final ThreadMXBean threadMXBean;

    static {
        threadMXBean = Management.getThreadMXBean();
        if (threadMXBean.isThreadCpuTimeSupported()) {
            USING_BEAN = true;
        } else {
            USING_BEAN = false;
        }
    }

    
Gets the current time of this thread in nanoseconds from the most accurate timer available on
the system. The returned value will be the current time in nanoseconds precision but not
necessarily nanoseconds accuracy.

The intended use case of this method is to measure the time a certain action takes by making
successive calls to it. It should not be used to measure total times in the sense of a time
stamp.
Returns:
the current thread's time in nanoseconds/**
     * Gets the current time of this thread in nanoseconds from the most accurate timer available on
     * the system. The returned value will be the current time in nanoseconds precision but not
     * necessarily nanoseconds accuracy.
     * <p>
     * The intended use case of this method is to measure the time a certain action takes by making
     * successive calls to it. It should not be used to measure total times in the sense of a time
     * stamp.
     *
     * @return the current thread's time in nanoseconds
     */
    public static long getTimeNS() {
        return USING_BEAN ? threadMXBean.getCurrentThreadCpuTime() : System.nanoTime();
    }

}