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Index › Programming Questions & Help › Syntax Questions › super() in a constructor

Phattee Junior Member Offline Posts: 89

super() in a constructor May 19th, 2009, 2:12pm   Hello, The following code fragment is from code 48-05 on pg 457 of the book "Processing": Quote: class SpinArm extends Spin {      SpinArm(float x, float y, float s) {     super(x, y, s);   } I understand that here super is calling the constructor of the superclass. How does the program know that it's calling for the constructor of Spin? How come it's not super.Spin(x, y, s)?

NoahBuddy Ex Member	Re: super() in a constructor Reply #1 - May 19th, 2009, 2:29pm   The call to super() is always to the class that your class extends. It works as if the compiler fills in the proper values for this: Code: this = new super();//Don't try this at home, kids Then tacks on the new stuff that your class contains.

PhiLho  YaBB Moderator Offline Posts: 4190 Near Paris (France)

Re: super() in a constructor Reply #2 - May 19th, 2009, 11:05pm   Phattee wrote on May 19th, 2009, 2:12pm: How does the program know that it's calling for the constructor of Spin How come it's not super.Spin(x, y, s) 1) A class can have only one parent (can be Object class). 2) super() is implicitly a call to the constructor of the parent, no need to give it by name. 3) If the parent has several constructors, they are distinguished by the number and kind (type) of the parameters of the call.