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

Nicole Favela
Nicole Favela
1,342 Points
Posted by Nicole Favela
Nicole Favela
1,342 Points

I don't understand what the question is asking. where do I place the method isFullyCharged?

do I need a while and an if statement and where should it be placed?
Is a return statement required?

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;
  }

}

2 Answers

Victor Learned
Victor Learned
6,976 Points
Victor Learned
Victor Learned
6,976 Points

You should be updating the charge() method to use a while loop that calls the isFullyCharged() function as your break case. Something like this:

public void charge(){
  //Look are how isFullyCharged is a method that returns a boolean value
  while(!isFullyCharged())
  {
      mBarsCount++;
  }
}
Nicole Favela
Nicole Favela
1,342 Points
Nicole Favela
Nicole Favela
1,342 Points

Oh, I see. Thanks, that really helps. Can you tell me why isFullyCharged doesn't have to be declared at the top like I've seen other booleans (e.g. private boolean isFullyCharged or isBatteryEmpty)?

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

Hi Nicole,

To answer your question about isFullyCharged, it is a method, and not a variable. Variables get declared at the top. Methods (or functions) do work on variables, and often return a result. The result can be a value like "true" or "false", so calling a method that returns a result gives you a similar value to calling a variable that holds a value.

Please let me know if that was helpful. :)