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Java Java Objects Harnessing the Power of Objects Overload Methods

Kyle Dudley
Kyle Dudley
604 Points
Posted by Kyle Dudley
Kyle Dudley
604 Points

how?

idk

GoKart.java 
class GoKart {
  public static final int MAX_BARS = 8;
  private String color;
  private int barCount;
  private int lapsDriven;
  private int laps;

  public GoKart(String color) {
    this.color = color;
  }

  public String getColor() {
    return color;
  }
  public void charge() {
    barCount = MAX_BARS;
  }

  public boolean isBatteryEmpty() {
    return barCount == 0;
  }

  public boolean isFullyCharged() {
    return MAX_BARS == barCount;
  }

  public void drive() {
    lapsDriven++;
    barCount--;
    laps == 6;
  }
}

2 Answers

Amrit Pandey
Amrit Pandey
17,595 Points
Amrit Pandey
Amrit Pandey
17,595 Points

It's simple. You see, our people say that, the program we created only allows them to drive their car for just one LAP. They need more laps. Now closely see this drive function.

  public void drive() {
    lapsDriven++;
    barCount--;
  }

When you power up your vehicle to make a lap, you will use drive() method to complete one lap. Then you will use drive() method to complete second lap. You will keep calling this method for n times for n number of laps.

How, about we specify this method to run our car for n times without calling it n times. Smart is'nt it?

So we pass a parameter which will be our lap number and, keep executing the method untill we complete the specified number of laps.

public void drive(int laps) {
    while(laps>lapsDriven){
      lapsDriven++;
      barCount--;
    }
  }

I hope you understood the concept. :)

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

There's a rather serious logic error in that. What happens when you've already driven some laps and want to drive more? (lapsDriven is not zero)

Amrit Pandey
Amrit Pandey
17,595 Points
Amrit Pandey
Amrit Pandey
17,595 Points

Can't We just initialize lapsDriven?

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

You can initialize it in the constructor but you'll still have the same issue. lapsDriven is supposed to be a record of the laps. If you drive(4) laps and then drive(2) you should have 6 lapsDriven and still be able to drive more.

Kyle Dudley
Kyle Dudley
604 Points
Kyle Dudley
Kyle Dudley
604 Points

Thanks for the answer!

Amrit Pandey
Amrit Pandey
17,595 Points
Amrit Pandey
Amrit Pandey
17,595 Points

sethkroger Yeah I understand that. lapsDriven is declared as global variable. Whatever value we increment is stored in lapsDriven

the drive method should be somewhat like this.

public void drive(int laps){
  int lapsOver;
  while(laps>lapsOver && this.isBatteryEmpty()){
    lapsOver+=1;
    barCount-=1;
  }
}

I am still starting, so take this as a pseudo code.