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Java Java Objects (Retired) Harnessing the Power of Objects Incrementing

Posted by Ahmed Alfatih
Ahmed Alfatih
Courses Plus Student 598 Points

help please

Okay, so let's use our new isFullyCharged helper method to change our implementation details of the charge method. Let's make it so it will only charge until the battery reports being fully charged. Let's use the ! symbol and a while loop. Inside the loop increment mBarsCount.

GoKart.java 
public class GoKart {
  public static final int MAX_ENERGY_BARS = 8;
  private String mColor;
  private int mBarsCount;

  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;
  }

  public String getColor() {
    return mColor;
  }

  public void charge() {
    mBarsCount = MAX_ENERGY_BARS;
  }

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

  public boolean isFullyCharged() {
    return mBarsCount == MAX_ENERGY_BARS;
  }

}
iftekhar uddin
iftekhar uddin
4,194 Points
iftekhar uddin
iftekhar uddin
4,194 Points

I think it's already answered down below but just for future reference it'll help people more if you explicitly describe what exactly you need help with :D

Ahmed Alfatih
Ahmed Alfatih
Courses Plus Student 598 Points

thanks

1 Answer

Derek Markman
Derek Markman
16,291 Points
Derek Markman
Derek Markman
16,291 Points

You place your while loop inside of the 'charge' method. 

public class GoKart {
  public static final int MAX_ENERGY_BARS = 8;
  private String mColor;
  private int mBarsCount;

  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;
  }

  public String getColor() {
    return mColor;
  }

//this is the only method you need to modify.
//this is where you place your while loop.  
public void charge() {
    while(!isFullyCharged()) {
      mBarsCount++;
    }
  }

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

  public boolean isFullyCharged() {
    return mBarsCount == MAX_ENERGY_BARS;
  }

}

Your while loop is checking if your go kart is fully charged, by using the boolean returned from the 'isFullyCharged' method. If your go kart is NOT fully charged (a.k.a mBarsCount is NOT equal to MAX_ENERGY_BARS) then increment mBarsCount.