java - Does subclass use always super-class's default constructor? -


this question has answer here:

why subclass not able use own default constructor? when bike extends vehicle class, why bike using vehicle's constructor creating bike object?

that seems okay use parent's class constructor when bike object having more additional members doesn't exist in parent class using super class decrease writing additional duplicate code initialize. looks okay.(might wrong).

public class vehicle {      vehicle()     {          system.out.println("vehicle created");      } }  public class bike extends vehicle {      public static void main(string[] args){          bike hondabike = new bike();         } }  output: vehicle created

new bike() invokes parameter-less constructor of class bike, invokes parameter-less constructor of super class vehicle, since didn't write parameter-less constructor class bike, compiler generated 1 empty body. therefore appears vehicle's constructor executed.


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