StopWatch (Apache Commons Lang 3.8 API)

java.lang.Object
- org.apache.commons.lang3.time.StopWatch

```
public class StopWatch
extends Object
```
StopWatch provides a convenient API for timings.

To start the watch, call start() or createStarted(). At this point you can:
- split() the watch to get the time whilst the watch continues in the background. unsplit() will remove the effect of the split. At this point, these three options are available again.
- suspend() the watch to pause it. resume() allows the watch to continue. Any time between the suspend and resume will not be counted in the total. At this point, these three options are available again.
- stop() the watch to complete the timing session.
It is intended that the output methods toString() and getTime() should only be called after stop, split or suspend, however a suitable result will be returned at other points.

NOTE: As from v2.1, the methods protect against inappropriate calls. Thus you cannot now call stop before start, resume before suspend or unsplit before split.

1. split(), suspend(), or stop() cannot be invoked twice
2. unsplit() may only be called if the watch has been split()
3. resume() may only be called if the watch has been suspend()
4. start() cannot be called twice without calling reset()

This class is not thread-safe
Since:

2.0

Constructor Summary

Constructors
Constructor and Description

StopWatch()
Constructor.

Constructors
Constructor and Description
`StopWatch()` Constructor.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static StopWatch`	`createStarted()` Provides a started stopwatch for convenience.
`long`	`getNanoTime()` Get the time on the stopwatch in nanoseconds.
`long`	`getSplitNanoTime()` Get the split time on the stopwatch in nanoseconds.
`long`	`getSplitTime()` Get the split time on the stopwatch.
`long`	`getStartTime()` Returns the time this stopwatch was started.
`long`	`getTime()` Get the time on the stopwatch.
`long`	`getTime(TimeUnit timeUnit)` Get the time on the stopwatch in the specified TimeUnit.
`boolean`	`isStarted()` The method is used to find out if the StopWatch is started.
`boolean`	`isStopped()` This method is used to find out whether the StopWatch is stopped.
`boolean`	`isSuspended()` This method is used to find out whether the StopWatch is suspended.
`void`	`reset()` Resets the stopwatch.
`void`	`resume()` Resume the stopwatch after a suspend.
`void`	`split()` Split the time.
`void`	`start()` Start the stopwatch.
`void`	`stop()` Stop the stopwatch.
`void`	`suspend()` Suspend the stopwatch for later resumption.
`String`	`toSplitString()` Gets a summary of the split time that the stopwatch recorded as a string.
`String`	`toString()` Gets a summary of the time that the stopwatch recorded as a string.
`void`	`unsplit()` Remove a split.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - StopWatch
```
public StopWatch()
```
    Constructor.
- Method Detail
  - createStarted
```
public static StopWatch createStarted()
```
    Provides a started stopwatch for convenience.
    
    Returns:
    
    StopWatch a stopwatch that's already been started.
    
    Since:
    
    3.5
  - start
```
public void start()
```
    Start the stopwatch.
    
    This method starts a new timing session, clearing any previous values.
    
    Throws:
    
    IllegalStateException - if the StopWatch is already running.
  - stop
```
public void stop()
```
    Stop the stopwatch.
    
    This method ends a new timing session, allowing the time to be retrieved.
    
    Throws:
    
    IllegalStateException - if the StopWatch is not running.
  - reset
```
public void reset()
```
    Resets the stopwatch. Stops it if need be.
    
    This method clears the internal values to allow the object to be reused.
  - split
```
public void split()
```
    Split the time.
    
    This method sets the stop time of the watch to allow a time to be extracted. The start time is unaffected, enabling unsplit() to continue the timing from the original start point.
    
    Throws:
    
    IllegalStateException - if the StopWatch is not running.
  - unsplit
```
public void unsplit()
```
    Remove a split.
    
    This method clears the stop time. The start time is unaffected, enabling timing from the original start point to continue.
    
    Throws:
    
    IllegalStateException - if the StopWatch has not been split.
  - suspend
```
public void suspend()
```
    Suspend the stopwatch for later resumption.
    
    This method suspends the watch until it is resumed. The watch will not include time between the suspend and resume calls in the total time.
    
    Throws:
    
    IllegalStateException - if the StopWatch is not currently running.
  - resume
```
public void resume()
```
    Resume the stopwatch after a suspend.
    
    This method resumes the watch after it was suspended. The watch will not include time between the suspend and resume calls in the total time.
    
    Throws:
    
    IllegalStateException - if the StopWatch has not been suspended.
  - getTime
```
public long getTime()
```
    Get the time on the stopwatch.
    
    This is either the time between the start and the moment this method is called, or the amount of time between start and stop.
    
    Returns:
    
    the time in milliseconds
  - getTime
```
public long getTime(TimeUnit timeUnit)
```
    Get the time on the stopwatch in the specified TimeUnit.
    
    This is either the time between the start and the moment this method is called, or the amount of time between start and stop. The resulting time will be expressed in the desired TimeUnit with any remainder rounded down. For example, if the specified unit is TimeUnit.HOURS and the stopwatch time is 59 minutes, then the result returned will be 0.
    
    Parameters:
    
    timeUnit - the unit of time, not null
    
    Returns:
    
    the time in the specified TimeUnit, rounded down
    
    Since:
    
    3.5
  - getNanoTime
```
public long getNanoTime()
```
    Get the time on the stopwatch in nanoseconds.
    
    This is either the time between the start and the moment this method is called, or the amount of time between start and stop.
    
    Returns:
    
    the time in nanoseconds
    
    Since:
    
    3.0
  - getSplitTime
```
public long getSplitTime()
```
    Get the split time on the stopwatch.
    
    This is the time between start and latest split.
    
    Returns:
    
    the split time in milliseconds
    
    Throws:
    
    IllegalStateException - if the StopWatch has not yet been split.
    
    Since:
    
    2.1
  - getSplitNanoTime
```
public long getSplitNanoTime()
```
    Get the split time on the stopwatch in nanoseconds.
    
    This is the time between start and latest split.
    
    Returns:
    
    the split time in nanoseconds
    
    Throws:
    
    IllegalStateException - if the StopWatch has not yet been split.
    
    Since:
    
    3.0
  - getStartTime
```
public long getStartTime()
```
    Returns the time this stopwatch was started.
    
    Returns:
    
    the time this stopwatch was started
    
    Throws:
    
    IllegalStateException - if this StopWatch has not been started
    
    Since:
    
    2.4
  - toString
```
public String toString()
```
    Gets a summary of the time that the stopwatch recorded as a string.
    
    The format used is ISO 8601-like, hours:minutes:seconds.milliseconds.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    the time as a String
  - toSplitString
```
public String toSplitString()
```
    Gets a summary of the split time that the stopwatch recorded as a string.
    
    The format used is ISO 8601-like, hours:minutes:seconds.milliseconds.
    
    Returns:
    
    the split time as a String
    
    Since:
    
    2.1
  - isStarted
```
public boolean isStarted()
```
    The method is used to find out if the StopWatch is started. A suspended StopWatch is also started watch.
    
    Returns:
    
    boolean If the StopWatch is started.
    
    Since:
    
    3.2
  - isSuspended
```
public boolean isSuspended()
```
    This method is used to find out whether the StopWatch is suspended.
    
    Returns:
    
    boolean If the StopWatch is suspended.
    
    Since:
    
    3.2
  - isStopped
```
public boolean isStopped()
```
    This method is used to find out whether the StopWatch is stopped. The stopwatch which's not yet started and explicitly stopped stopwatch is considered as stopped.
    
    Returns:
    
    boolean If the StopWatch is stopped.
    
    Since:
    
    3.2

Class StopWatch

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

StopWatch

Method Detail

createStarted

start

stop

reset

split

unsplit

suspend

resume

getTime

getTime

getNanoTime

getSplitTime

getSplitNanoTime

getStartTime

toString

toSplitString

isStarted

isSuspended

isStopped