Nov 12, 2008 · The keyword this can be used to call a constructor from a constructor, when writing several constructor for a class, there are times when you'd like to call one constructor from another to avoid duplicate code. Bellow is a link that I explain other topic about constructor and getters() and setters() and I used a class with two constructors.

Oct 14, 2012 · If you use this() or super() call in your constructor to invoke the other constructor, it should always be the first statement in your constructor. That is why your below code does not compile: - Foo(Double a) { Double b = a + 10; this(a, b); } You can modify it to follow the above rule: - Foo(Double a) { this(a, a + 10); //This will work.

Jul 9, 2013 · I was told that the way to call a constructor is type object_variable = new type i.e: Fraction f1 = new Fraction( 2, 3 ); but I also read on stackoverflow that the way to call a constructor is using the "this."

You can actually require a constructor for a generic type. It's not perfect but have a look at this: public interface Constructor<T> { T constructor() ; } It's a general purpose functional interface to describe every noArgs constructor. The java.util.function.Supplier can also be used as it …

Nov 5, 2016 · The class mpgCalculator only has the default constructor since you didn't define one. You don't call the constructor manually; instead, you create a new object and it's called automatically. You probably want this: mpgCalculator calc = new mpgCalculator();

Oct 31, 2014 · Also, in the constructor method, you are overwriting the value of size given by you earlier. Thus, there is practically no need to supply the variable to the method. Thus, there is practically no need to supply the variable to the method.

The constructor is called only once, so you can safely do what you want, however the disadvantage of calling methods from within the constructor, rather than directly, is that you don't get direct feedback if the method fails. This gets more difficult the more methods you call.

Mar 8, 2015 · The standard way of calling a Java constructor is like this: ClassA theClass = new ClassA(); If your constructor accepts parameters (say, three ints), then you can modify your code to this: ClassA theClass = new ClassA(10, 20, 30);

Nov 8, 2011 · Rather than completely replace the constructor for the parent class, I want to call the parent class's constructor first, and then do some extra work. I believe that by default the parent class's 0 arguments constructor is called. This isn't what I want. I need the constructor to be called with an argument. Is this possible? I tried

1.'this' Keyword refers to object of class where it is used.Generally we write instance variable,constructors and methods in class.All this members are represented by 'this'. 2.When an object is created to a class,a default reference is also created internally to the object.It's nothing but 'this'. 3.Example for this keyword: Sample(int x ...