Question

Suppose I have the following classes:

class A {}
class B extends A {}

A instA = new A();
A instB = new B();

Now as far Java is concerned instB is of type A.

How can I find out what is instB’s actual type?

Answer 1

You can use instB.getClass(). This will return a Class object representing instB‘s runtime type.

Source: javadoc

You can also use the following conditional check with instanceof:

if (instB instanceof B) {
    //then we know it is of type B
}

instanceof would be the more conventional way, and the conditional will also return true if instB is a subclass of B.

You may want to further explain your use case, with code examples, to get better discussion.