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

Blake Larson
Blake Larson
13,014 Points

While loop in class file.

In the video tutorial he put the while loop in the example.java file and in the code challenge it asks me to put the while loop in the class file. Not sure how to do this.

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 boolean charging() {
   boolean wasCharging = false;
    if(!isFullyCharged()) {
      mBarsCount++;
      wasCharging = true;
    }
    return wasCharging;
  }



  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;
  }

}
Blake Larson
Blake Larson
13,014 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.

This is the challenge.

1 Answer

you have to change the charge method, so that it will only increment mBarsCount as long as the isFullyCharged is false.

this how the code should look like:

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() {
    while (!isFullyCharged()){
      mBarsCount++;
    }
  }

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

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

}
Blake Larson
Blake Larson
13,014 Points

Thank you for the help. That makes more sense. I was trying to format it like it was in the video.

your welcome anytime.