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Java Java Objects Meet Objects Add a Constructor

Posted by Nikolai Pütz
Nikolai Pütz
965 Points

I dont understand why we need a constructor

We have

private String color;

and we can return it with our method why we need a constructor that sets the color to color?

GoKart.java 
class GoKart {
  private String color;

  public GoKart (String color){
  this.color = color;
  }

  public String getColor() {
    return color;
  }

}

1 Answer

Benjamin Dahlhoff
Benjamin Dahlhoff
4,484 Points

Color is a private variable and therefore not accessible outside the class. This is where the getters and setters come in. They help you to modify or read the variables. The constructor itself can be designed in the way you like to set up all the variables in on step. You designed a default constructor with a String you are passing. but you could also have it empty, set a default color and later and pass a new one with a setter-method.

class GoKart {
   private String mColor;

   public GoKart () {
      mColor = "Black";
   }

   public void setColor(String someColor) {
      mColor = someColor;
   }

   public String getColor() {
      return mColor;
   }
}