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Java Java Objects (Retired) Harnessing the Power of Objects Methods and Constants

Posted by Brandyn lee murtagh
Brandyn lee murtagh
432 Points

Harnessing the power of objects challenge

So, could anyone walk me through the question :

Finally, let's add a method named charge. It should be public and return nothing. When called it should set mBarsCount to the value of the constant you declared in Task 1.

Please? I only need guidance on the last part of the question.

GoKart.java 
public class GoKart {
  private String mColor;
  public static final int MAX_BAT = 8;
  private int mBarsCount;
  public int charge;


  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;
  }
  public String getColor() {
    return mColor;
  } 
}

2 Answers

Mikael Enarsson
Mikael Enarsson
7,056 Points
Mikael Enarsson
Mikael Enarsson
7,056 Points

The question is asking you to make a method called charge, but you have made a field.

The difference is that a field is something that holds a value, for example:

private String mColor;
private int mBarsCount;
public static final int MAX_CHARGE = 8;

are all fields, holding a String, an int and an int respectively.

A method, on the other hand, is a behavior, that is, a piece of code that allows you to see or manipulate data, such as:

public String getColor() { //this is the method name. 
                           //You call the method using [object name].[method name]()
                           //for non-static methods
  return mColor;           //this methods returns the value of mColor
}

and

public void setColor(String color) {
  mColor = color;            //this method sets the value of mColor to the provided value
}

get and set methods are especially important for encapsulation, I find.

I hope that this is enough information to help you through, but if you have any other questions, don't hesitate to ask ^^

Brandyn lee murtagh
Brandyn lee murtagh
432 Points

Hi mate i've been stuck on this for ages and its still really annoying me.. I understand a lot more due to that response but I still cant seem to get it!

This is my code so far:

GoKart.java 
public class GoKart {
  private String mColor;
  public static final int MAX_BAT = 8;
  private int mBarsCount;

  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;  
  }
  public void Charge() {
    mBarsCount = MAX_BAT

  }
  public String getColor() {
    return mColor;
  } 
}
Mikael Enarsson
Mikael Enarsson
7,056 Points
Mikael Enarsson
Mikael Enarsson
7,056 Points

Oh, sorry, I didn't see that you had updated the comment with the code! It's as Craig says, otherwise everything looks good!

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher
Craig Dennis
Craig Dennis
Treehouse Teacher

Brandyn lee murtagh ,

Your charge method has an uppercase C. And you are missing a semi-colon. Other than that, looks good!

Brandyn lee murtagh
Brandyn lee murtagh
432 Points

hey thanks for your reply.. still doesn't work though and I don't know why :/

UPDATE: I have done it! I accidentally deleted a '}'

Mikael Enarsson
Mikael Enarsson
7,056 Points
Mikael Enarsson
Mikael Enarsson
7,056 Points

I just tried it and passed. Could you post your current code?