Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

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

Chris Tapia
Chris Tapia
1,684 Points
Posted by Chris Tapia
Chris Tapia
1,684 Points

Java Objects Increment/Decrement

I'm not sure what I did wrong...I know I need to implement a while loop but I'm unsure of how to do this because unlike the PEZ example, where there is a while declaration in Example file, this canvas only has GoKart.java. Im just confused on where to put the while loop...

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 wasCharged = false;
    if(!isBatteryEmpty()) {
     mBarsCount++;

      wasCharged = true;
    }


  }

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

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


  }

}

1 Answer

warborn
warborn
7,116 Points
warborn
warborn
7,116 Points

Hi Chris, the only thing you need to do in this task is to change the change method implementation, so, initially the code for that method is this:

public void charge() {
    mBarsCount = MAX_ENERGY_BARS;
  }

The instructions says you need to charge the battery while is not at it's fullest, you need to use a while loop to charge the battery (increment mBarsCount)

while (condition) {
  mBarsCount++;
}

For the condition the instructions tells you to use the new isFullyCharged method and the ! (not operator), in english the condition will be this, "while is not fully charged i want to charge the battery", the resultant code is this:

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

Sorry for bad english