Stopwatch

```
public class Stopwatch
extends Object
```
A simple timer class based on elapsed wall-clock time. May be stopped and started under program control, and provides both accumulated time and time since last started in units of msec. At any given point, a given timer has some number of properly nested subtimers running. While one subtimer is running, you can start and stop another, allowing you to time parts of some larger activity while still computing the time for the entire activity.

Constructors
Constructor and Description
`Stopwatch()` A stopped timer (! isRunning ()) with 0msec accumulated time.

Methods
Modifier and Type	Method and Description
`long`	`getAccum()` The total time in milliseconds that isRunning () has been true since THIS was created or reset.
`long`	`getElapsed()` The time in milliseconds since the latest, still-running subtimer started.
`int`	`getRunning()` The number of nested subtimers currently running.
`boolean`	`isRunning()` True iff there are subtimers of THIS running.
`void`	`reset()` Stop all subtimers, and set accumulated time to 0.
`void`	`start()` Start a new subtimer at the current time.
`long`	`stop()` Stops the most recently started, still-running subtimer, returning the time elapsed since it started in milliseconds.

Class Stopwatch