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Java Java Objects (Retired) Meet Objects Privacy and Methods

Posted by adsdev
adsdev
15,583 Points

Explanation please :(

I have a question about some parts of the code. I finished it and all correctly but i don't entirely understand the thought behind it. The color variable is private, so i can assume that is only visible to the GoKart class and instances of it (objects right ?). Furthermore I have a headache about this xP :

If I use the getColor method in another object from another class, is this possible or not because of the private visibility ? Does it have to become a package or something ?

GoKart.java 
public class GoKart {
  private String mColor = "red";

  public String getColor(){
   return mColor; 
  }
}
Joseph Nickalo
Joseph Nickalo
432 Points

I´m on this lesson and I can already tell that I will be going through hell lol. x_x

1 Answer

Jon Kussmann
PLUS
Jon Kussmann
Courses Plus Student 7,254 Points
Jon Kussmann
Jon Kussmann
Courses Plus Student 7,254 Points

Let's see if this helps:

You are correct in saying that a private variable can only be accessed within the class that it is defined (in this case mColor). This is why you CAN use it in the method getColor().

Now, if you had a different class such as... a Track class and you instantiate a new GoKart:

GoKart goKart = new goKart();

You cannot get the color through

goKart.mColor;

since mColor is private.

You can however use

goKart.getColor();

since that method is public. The fact that the getColor() method "uses" mColor does not matter because that is being run "within" the GoKart class, and not the Track class.

adsdev
adsdev
15,583 Points

just for verification, because i get the rest, if i would be in the Track class, i would need to use the goKart.getColor() method to reach the mColor variable of the GoKart Class right ?

adsdev
adsdev
15,583 Points

Alright, thanks a lot :D !