Constructors in abstract classes? [duplicate]

Answer 1

By adding a constructor to an abstract class you can force the child classes to make a call to super in order to initialize some fields. Example:

abstract class Person {
   private String name;
   public Person(String name) {
      this.name = name;
   }
}

class SoccerPlayer extends Person {
   public SoccerPlayer(String name) {
     super(name);
   }
}
Person p = new SoccerPlayer("Ronaldo");