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

Posted by Clayton Roberts
Clayton Roberts
2,109 Points

I am unclear on where/how to use the while loop on Challenge Task

On the Challenge Task "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." I am unclear on where I put my while loop. Please help

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

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

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

}
Jeremy Hill
Jeremy Hill
29,567 Points

It wants you to incorporate the "isFullyCharged()" method and the only way to do that is to say while(! isFullyCharged()) and then increment the counter in the code block under it.

I hope this helps.

3 Answers

Jeremy Hill
Jeremy Hill
29,567 Points 
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;
    while(!(this.isFullyCharged())){
      mBarsCount++;
    }
  }

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

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

}
Clayton Roberts
Clayton Roberts
2,109 Points

Thank you so much

Jeremy Hill
Jeremy Hill
29,567 Points

You're welcome :)

Stephen Wall
Stephen Wall
Courses Plus Student 27,294 Points
Stephen Wall
Stephen Wall
Courses Plus Student 27,294 Points

Hmmm not sure about this, seems like it is setting the bars count immediately to the max amount before even running the loop.

Stephen Wall
PLUS
Stephen Wall
Courses Plus Student 27,294 Points
Stephen Wall
Stephen Wall
Courses Plus Student 27,294 Points

Heres what I got.

public void charge(){ while(!isFullyCharged()){ mBarsCount++; } }

Stephen Wall
PLUS
Stephen Wall
Courses Plus Student 27,294 Points
Stephen Wall
Stephen Wall
Courses Plus Student 27,294 Points 
public void charge(){
while(!isFullyCharged()){
mBarsCount++; 
  }
}