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Java Java Objects (Retired) Meet Objects Constructors

Posted by Venzislav Simeonov
Venzislav Simeonov
351 Points

I'm stuck!

I cant understand the question.Add a public constructor to the GoKart.java class that allows the parameter color to be passed in. In the constructor store the argument color in the private color field.

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

  public String getColor() {
    return mColor;
  }
}

2 Answers

Geovanie Alvarez
Geovanie Alvarez
21,500 Points
Geovanie Alvarez
Geovanie Alvarez
21,500 Points 
public class GoKart {
  private String mColor = "red";

  public GoKart(String color){ // <----- public constructor and parameter
    mColor = color; // <----- assign the mColor variable to the parameter variable
  }

  public String getColor() {
    return mColor;
  }
}
Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hi Venzislav,

a constructor is helping you to create objects of a class (here GoKart) and add parameters to them (here color).

To create a new object of the GoKart class you would write (not needed for the challenge):

GoKart gk = new GoKart(red)

On the right side of the line you are writing "new GoKart(red)" and this calls the constructor that accepts a String "red" as color for your GoKart. So gk is the object of the GoKart class that has the color "red".

To ensure that the constructor works properly you must follow some naming conventions. The name of the constructor must be the same as the class. Constructors return nothing and take different arguments (in this challenge a String representation of the color).

To create a constructor your code could look like this:

public GoKart(String color) {
    mColor = color;
  }

Hope that helps :)

Grigorij