Miscellaneous Terms with Polymorphism

The keyword instanceof is used to test if an object "isa" particular class.
This will return true if the object is the specified class, or if it is a child class:
```
if (object instanceof Class) 
```

You can also use reflection (also call introspection) to examine the class of an object.
This is done with a group of classes that are in the java.lang.reflect package (what is your import statement?).
You can get the class of an object with the getClass() method, which returns a object of class Class
Yes, Class is the actual name of the class in this case:
```
Class   aClass = "string".getClass();
if (object.getClass() == SomeClass.class) 
    ...
```
Every object has the getClass()method - why is this?

There may be times when your code needs to revert to a reference of the child class; this is done by downcasting.

First use instanceof to make sure it is the right child class, the assign it with the down-cast:

if (object instanceof Child)
{
    Child ref = (Child)object;
    // now you can call methods that are only in the child class using ref.
}

Note:

You CAN assign an object of the child-class to a reference of the parent-class (this is polymorphism).
You CANNOT assign an object of the parent-class to a reference of the child-class.