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

Robert Walsh
Robert Walsh
802 Points
Posted by Robert Walsh
Robert Walsh
802 Points

Stuck on This Challenge (Java Objects) Decrementing and While Loops

Need help with the syntax...

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() {
      boolean wasDispensed = false;
    if(!isFullyCharged()){
     mBarsCount--;
    }
    return mBarsCount == MAX_ENERGY_BARS;

    while(mBarsCount.isFullyCharged()){

    }

}
Robert Walsh
Robert Walsh
802 Points
Robert Walsh
Robert Walsh
802 Points

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.

3 Answers

Jess Sanders
Jess Sanders
12,086 Points
Jess Sanders
Jess Sanders
12,086 Points

Use the following snippet of code as your example to follow in changing the implementation details of the charge method:

public boolean dispense() {
    boolean wasDispensed = false;
    if (!isEmpty()) {
      mPezCount--;
      wasDispensed = true;
    }
    return wasDispensed;
  }
  • Instead of if, use while
  • increment, rather than decrement
  • The charge method doesn't need to return a boolean, so ignore all of the code involving the boolean wasDispensed

Keep isFullyCharged as it was from the previous challenge.

  public boolean isFullyCharged() {
    return mBarsCount == MAX_ENERGY_BARS;
  }
Michael C
Michael C
3,230 Points
Michael C
Michael C
3,230 Points

use in the while loop following logic -> "!isBatteryEmpty" - which means "If the battery is NOT Empty then return true". While this condition is actually true you can increment mBarCount by "1". If the Battery then is finally full the logic will return "false" and the while loop will break - in fact it will stop charging up the battery

Jeeya M
Jeeya M
16,839 Points
Jeeya M
Jeeya M
16,839 Points

Also you wrote boolean wasDispensed = false; which isn't apart of this activity, only in the video