How do I call one constructor from another in Java?

Question

Is it possible to call a constructor from another (within the same class, not from a subclass)? If yes how? And what could be the best way to call another constructor (if th

Answer 1

Yes, any number of constructors can be present in a class and they can be called by another constructor using this() [Please do not confuse this() constructor call with this keyword]. this() or this(args) should be the first line in the constructor.

Example:

Class Test {
    Test() {
        this(10); // calls the constructor with integer args, Test(int a)
    }
    Test(int a) {
        this(10.5); // call the constructor with double arg, Test(double a)
    }
    Test(double a) {
        System.out.println("I am a double arg constructor");
    }
}

This is known as constructor overloading.
Please note that for constructor, only overloading concept is applicable and not inheritance or overriding.