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Java Java Objects (Retired) Meet Objects Constructors

Posted by Chris Rinaldi
Chris Rinaldi
Courses Plus Student 407 Points

Null pointer? Why, i don't understand.

public class GoKart { private String mColor; public GoKart(String color) { color = mColor; } public String getColor() { return mColor; }

}

GoKart.java 
public class GoKart {
  private String mColor;
  public GoKart(String color) {
    color = mColor;
  }
  public String getColor() {
    return mColor;
  }

}

1 Answer

Chris Adamson
Chris Adamson
132,143 Points
Chris Adamson
Chris Adamson
132,143 Points

In your constructor you have the assignment backwards:

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

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

  public String getColor() {
    return mColor;
  }
}
Chris Rinaldi
Chris Rinaldi
Courses Plus Student 407 Points

Thank you very much :)

Chris Rinaldi
Chris Rinaldi
Courses Plus Student 407 Points

Thank you very much :)