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

Solomon Alexandru
Solomon Alexandru
3,633 Points
Posted by Solomon Alexandru
Solomon Alexandru
3,633 Points

What am I doing wrong?

I'm struggling for a while with this exercise and I can't seem to get past it

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;
    while (mBarsCount != MAX_ENERGY_BARS) {
        return mBarsCount++;
    }
  }

}

2 Answers

Vrezh Gulyan
Vrezh Gulyan
11,161 Points
Vrezh Gulyan
Vrezh Gulyan
11,161 Points

First of all reset the code to what it was before this challenge. Remove

while (mBarsCount != MAX_ENERGY_BARS) {
        return mBarsCount++;
    }

Next what the challenge is asking you to do is to increment the number of energy bars as long as the battery is not fully charged. This is really easy since you just made a helper method called isFullyCharged which returns true once the battery level == 8 which is the max level. All you have to do is keep checking that isFullyCharged method and if it isnt full then you keep adding(charging) to the battery level. Since you are going to keep doing the same thing over and over you should see immediately that this is the job for a loop. So your charge method should now look like this:

public void Charge() {
     // Will return false until battery is full
      while( isFullyCharged == false){
      //increment bars
      mBarsCounts++;
      }
}
Seth Reece
Seth Reece
32,867 Points
Seth Reece
Seth Reece
32,867 Points

Hi Solomon,

Two thing here. I believe you want your while loop inside the charge method. Second the challenge is asking to use the isFullyCharged method. You loop should be structured: 

while (!isFullyCharged()) {
    mBarsCount++;
}
Seth Reece
Seth Reece
32,867 Points
Seth Reece
Seth Reece
32,867 Points

Here's the full passing code:

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;
  }

}