Compiler calls to no-arg super() in argumented constructors of child classes in java -

here goes:

public class parent {      public parent(string name) {         this.name = name;     }      public string name = null;  }  public class child extends parent {      public child(string name) {         super(name); // if comment : implicit super constructor parent() undefined. must explicitly invoke constructor     }  } 

it said "if don't invoke super constructor self, compiler insert no-arg call super() you, first statement in constructor."

• is true argument-ed constructors well?
• mustn't compiler call argument-ed super constructor same signature of child constructor?
• why has been designed this?

is true argument-ed constructors well?

yes.

mustn't compiler call argument-ed super constructor same signature of child constructor?

no. if want different base-class constructor invoked, must call yourself, passing arguments necessary.

why has been designed this?

because alternative you're proposing (automatically forwarding arguments) wouldn't useful in general.