Learn Java Programming - Instanceof Operator Tutorial
The first thing that we need to understand is the definition of a supertype. A supertype is a class or interface that is higher up the inheritance hierarchy. The instanceof operator compares an object(instance) to the Name of a supertype and returns a boolean result. The instanceof operator will also return true if the instance is of the same class name.
(reference variable) instanceof (Name of supertype)
String s = "Hello World";
s instanceof Object; // true