Write a class LapTimer that can be used to time the laps in a race. The class sh

Question

Write a class LapTimer that can be used to time the laps in a race. The class should have the following member variables (all private):

running - a boolean indication of whether the timer is running.

startTime - the time when the timer started

lapStart - the timer's value when the current lap started

lapTime - the elapsed time for the last lap

totalTime - the total time from the start of the race through the last completed lap

lapsCompleted - the number of laps completed so far

lapsInRace - the number of laps in the race

The class should have a single constructor that takes an integer n signifying the number of laps. In addition, the class should contain the following methods:

start starts the timer. Throws a TimerStateException if the race has already started.

markLap marks the end of the current lap and the start of a new lap. Throws a TimerStateException if the race has finished

getLapTime returns the time of the last lap. Throws a TimerStateException if the first lap has not yet been completed.

getTotalTime returns the total time from the start of the race through the last completed lap. Throws a TimerStateException if the first lap has not yet been completed.

getLapsRemaining returns the number of laps yet to be completed including the current one.

You should express all times in milliseconds. To get the current time in milliseconds from some baseline date, you should use the following code:

This returns a primitive of type long, which is equivalent to an integer with a larger MAX_VALUE. You will need to import java.util.Calendar to use this

To find the elapsed time, you can take the difference between two values obtained from the above code.

Explanation / Answer

import java.lang.System;

import java.util.Calendar;

public class LapTimer
{
private boolean running;
private int lapsInRace;
private long totalTime;
private long lapTime;
private int avgSpeed;
private int lapLength;
private long startTime;
private long lapEndTime;


public LapTimer()
{
running = false;
lapsInRace = 0;
lapTime = 0;
totalTime = 0;
lapTime = 0;
avgSpeed = 0;
lapLength = 400;
startTime = getSystemTime();
}


public void startLap()
{
running=true;
if(getSystemTime()> startTime)
{
lapTime=(getSystemTime() - startTime);
}
totalTime = (totalTime + lapTime);
startTime=getSystemTime();
lapsInRace++;
}


public void stop()
{
running = false;
lapTime = (getSystemTime() - startTime);
startTime = 0;
}


public String getStatus()
{
if(running = false)
{
return "Stopped";
}
else
{
return "Timing";
}
}


public int getLapsInRace()
{
return lapsInRace;
}


public String getLapTime()
{
String lapTimeString = Long.toString(lapTime);
return lapTimeString;
}

public String getAverageTime()
{
long averageTime;
if(lapsInRace!=0)
{
averageTime = totalTime/lapsInRace;
}
else
{
averageTime = totalTime;
}
String averageTimeString = Long.toString(averageTime);
return averageTimeString;
}

public String getTotalTime()
{
String totalTimeString = timeToString(totalTime);
return totalTimeString;

}


public String getAverageSpeed()
{
return "unfinished";
}


public int getLapLength()
{
return lapLength;
}


public void setLapLength(int length)
{
lapLength = length;
}


private void finishLap()
{

}


private String timeToString(long time)
{
int totalSeconds;
int hours;
int remainingMinutes;
int minutes;
int seconds;
totalSeconds = (int)totalTime/1000;
hours = totalSeconds/3600;
remainingMinutes=totalSeconds%3600;
minutes=remainingMinutes/60;
seconds = remainingMinutes%60;
String timeString = Long.toString(hours + minutes + seconds);
return timeString;

}


private String twoDigit(long number)
{

return "unfinished";
}


private long getSystemTime()
{
return System.currentTimeMillis();
}

}

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