Why do this() and super() have to be the first statement in a constructor?

Question

Java requires that if you call this() or super() in a constructor, it must be the first statement. Why?

For example:

public class MyClass {
    publi         


        

Answer 1

I found a woraround.

This won't compile :

public class MySubClass extends MyClass {
    public MySubClass(int a, int b) {
        int c = a + b;
        super(c);  // COMPILE ERROR
        doSomething(c);
        doSomething2(a);
        doSomething3(b);
    }
}

This works :

public class MySubClass extends MyClass {
    public MySubClass(int a, int b) {
        this(a + b);
        doSomething2(a);
        doSomething3(b);
    }

    private MySubClass(int c) {
        super(c);
        doSomething(c);
    }
}