Call a method after the constructor has ended

Question

I need to call a method after the constructor has ended and I have no idea how to do. I have this class:

Class A {
    public A() {
        //...
    }

    public void init() {
        //Call after the constructor
    }
}

Answer 1

You either have to do this on the client side, as so:

A a = new A();
a.init();

or you would have to do it in the end of the constructor:

class A {
    public A() {
        // ...
        init();
    }

    public final void init() {
        // ...
    }
}

The second way is not recommended however, unless you make the method private or final.

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Another alternative may be to use a factory method:

class A {
    private A() {  // private to make sure one has to go through factory method
        // ...
    }
    public final void init() {
        // ...
    }
    public static A create() {
        A a = new A();
        a.init();
        return a;
    }
}

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