Apr 13, 2010 · You may call super() with parameters if you want to call a non-default constructor of the superclass, or if the superclass does not have a default constructor. The compiler can only insert the default, no arguments super() constructor.

May 9, 2012 · A call to your parent class's empty constructor super() is done automatically when you don't do it yourself. That's the reason you've never had to do it in your code. It was done for you. When your superclass doesn't have a no-arg constructor, the compiler will require you to call super with the appropriate arguments. The compiler will make ...

Oct 2, 2012 · If a public no-argument (A.K.A. default) constructor exists in the superclass and is not explicitly defined in the subclass, and if the subclass also does not have any explicitly defined overloaded constructors (that is, constructors with parameters), then the compiler will automatically insert into the subclass a public no-argument constructor ...

Sep 22, 2010 · super calls a constructor in the superclass; this calls a constructor in this class : public MyClass(int a) { this(a, 5); // Here, I call another one of this class's constructors. } public MyClass(int a, int b) { super(a, b); // Then, I call one of the superclass's constructors. } super is useful if the superclass needs to initialize itself.

@ipinto.eu while your answer is correct and so is your solution, your last alternative solution in your answer (using setters of superclass) violates the rule of inheritance, I suppose, as it would give the "Overridable method call in constructor" problem. Hence, you last alternative solution is not an actual solution, but would bring bugs ...

Oct 3, 2018 · The constructor is simply a special method that allows you to execute some code before the object is created. Person p = new Person("Bob", 25); // Calls constructor Person(String name, int age) Then in the constructor you can do things …

The super line specifies how to call the superclass's constructor. It needs to be in there because there's no constructor for the superclass without parameters. A superclass constructor must be called, there's only one available constructor, and that constructor needs the name argument to …

In constructor, you need to call super() as a first statement (if you call it explicitly). On regular methods you call it wherever you want depending on your app logic needs. For example at the beginning if you want to add extra steps after call or at the end if you add extra check. –

Nov 12, 2008 · You can call another constructor via the this(...) keyword (when you need to call a constructor from the same class) or the super(...) keyword (when you need to call a constructor from a superclass). However, such a call must be the first statement of your constructor. To overcome this limitation, use this answer.

Mar 17, 2018 · I think you have to call super constructor first. You can try it. public class Date { public int month; public int day; public int year; Date() Date(int passedMonth, int passedDay, int passedYear){ month = passedMonth; day = passedDay; year = passedYear; } Then use it first in the constructor before your class constructor.