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Java 1.8+ Library with tons of utility classes required in all projects
/*
* Copyright (C) 2014-2022 Philip Helger (www.helger.com)
* philip[at]helger[dot]com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.helger.commons.timing;
import java.time.Duration;
import javax.annotation.Nonnegative;
import javax.annotation.Nonnull;
import javax.annotation.concurrent.NotThreadSafe;
import com.helger.commons.CGlobal;
import com.helger.commons.annotation.ReturnsMutableCopy;
import com.helger.commons.state.EChange;
import com.helger.commons.state.IStoppable;
import com.helger.commons.string.ToStringGenerator;
/**
* Simple stop watch based on {@link System#nanoTime()}.
*
* @author Philip Helger
*/
@NotThreadSafe
public class StopWatch implements IStoppable
{
private long m_nStartDT = 0;
private long m_nDurationNanos = 0;
/**
* Constructor.
*
* @param bStart
* if true the stop watch is directly started!
*/
protected StopWatch (final boolean bStart)
{
if (bStart)
start ();
}
/**
* Reset all saved durations, in case this stop watch is to be used in a loop.
* Does not change the start/stop state.
*
* @return {@link EChange}.
*/
@Nonnull
public EChange reset ()
{
if (m_nDurationNanos == 0)
return EChange.UNCHANGED;
m_nDurationNanos = 0;
return EChange.CHANGED;
}
/**
* @return The current time in nano seconds.
*/
protected static final long getCurrentNanoTime ()
{
return System.nanoTime ();
}
/**
* Start the stop watch.
*
* @return {@link EChange}.
*/
@Nonnull
public final EChange start ()
{
// Already started?
if (m_nStartDT > 0)
return EChange.UNCHANGED;
m_nStartDT = getCurrentNanoTime ();
return EChange.CHANGED;
}
/**
* Stop the stop watch.
*
* @return {@link EChange#CHANGED} if the stop watch was previously running
* and is now stopped, and {@link EChange#UNCHANGED} if the stop watch
* was already stopped.
*/
@Nonnull
public EChange stop ()
{
// Already stopped?
if (m_nStartDT == 0)
return EChange.UNCHANGED;
final long nCurrentNanoTime = getCurrentNanoTime ();
m_nDurationNanos += (nCurrentNanoTime - m_nStartDT);
m_nStartDT = 0;
return EChange.CHANGED;
}
/**
* Stops, resets and starts the stop watch.
*
* @see #stop()
* @see #reset()
* @see #start()
*/
public void restart ()
{
stop ();
reset ();
start ();
}
/**
* @return true if the stop watch is currently started (running),
* false otherwise.
*/
public boolean isStarted ()
{
return m_nStartDT > 0;
}
/**
* @return true if the stop watch is currently stopped (not
* running), false otherwise.
*/
public boolean isStopped ()
{
return m_nStartDT == 0;
}
/**
* @return The elapsed nano seconds (1000 nano seconds = 1 milli second).
*/
@Nonnegative
public long getNanos ()
{
return m_nDurationNanos;
}
/**
* @return The elapsed milli seconds.
*/
@Nonnegative
public long getMillis ()
{
return m_nDurationNanos / CGlobal.NANOSECONDS_PER_MILLISECOND;
}
/**
* @return The elapsed seconds.
*/
@Nonnegative
@Deprecated
public long getSeconds ()
{
return m_nDurationNanos / CGlobal.NANOSECONDS_PER_SECOND;
}
/**
* @return The elapsed duration. Never null.
*/
@Nonnull
public Duration getDuration ()
{
return Duration.ofNanos (m_nDurationNanos);
}
/**
* Stop the stop watch and get the elapsed nanoseconds since the start. If the
* stop watch was started and stopped multiple times, the duration is added.
*
* @return The elapsed nano seconds or 0 if the stop watch was never started.
*/
@Nonnegative
@Deprecated
public long stopAndGetNanos ()
{
stop ();
return getNanos ();
}
/**
* Stop the stop watch and get the elapsed milliseconds since the start. If
* the stop watch was started and stopped multiple times, the duration is
* added.
*
* @return The elapsed milli seconds or 0 if the stop watch was never started.
*/
@Nonnegative
public long stopAndGetMillis ()
{
stop ();
return getMillis ();
}
/**
* Stop the stop watch and get the elapsed seconds since the start. If the
* stop watch was started and stopped multiple times, the duration is added.
*
* @return The elapsed seconds or 0 if the stop watch was never started.
*/
@Nonnegative
@Deprecated
public long stopAndGetSeconds ()
{
stop ();
return getSeconds ();
}
/**
* Stop the stop watch and get the duration since the start. If the stop watch
* was started and stopped multiple times, the duration is added.
*
* @return The elapsed duration or 0 if the stop watch was never started.
*/
@Nonnull
public Duration stopAndGetDuration ()
{
stop ();
return getDuration ();
}
/**
* Create an intermediate time (lap time). It internally stops, takes the
* duration and restarts.
*
* @return The elapsed duration or 0 if the stop watch was never started.
* @since 10.0.0
*/
@Nonnull
public Duration getLapDuration ()
{
stop ();
final Duration ret = getDuration ();
start ();
return ret;
}
@Override
public String toString ()
{
return new ToStringGenerator (this).append ("StartDT", m_nStartDT).append ("DurationNanos", m_nDurationNanos).getToString ();
}
/**
* @return A new {@link StopWatch} object that is started. Never
* null.
*/
@Nonnull
@ReturnsMutableCopy
public static StopWatch createdStarted ()
{
return new StopWatch (true);
}
/**
* @return A new {@link StopWatch} object that is NOT started. Never
* null.
*/
@Nonnull
@ReturnsMutableCopy
public static StopWatch createdStopped ()
{
return new StopWatch (false);
}
/**
* Run the passed runnable and measure the time. In v10 this was changed to
* return Duration instead of TimeValue.
*
* @param aRunnable
* The runnable to be executed. May not be null.
* @return The elapsed Duration. Never null.
*/
@Nonnull
public static Duration runMeasured (@Nonnull final Runnable aRunnable)
{
final StopWatch aSW = createdStarted ();
aRunnable.run ();
return aSW.stopAndGetDuration ();
}
}