java: Class.isInstance vs Class.isAssignableFrom

Question

Let clazz be some Class and obj be some Object.

Is

clazz.isAssignableFrom(obj.getClass())

always the same as

clazz.isInstance(obj)

?

If not, what are the differences?

Answer 1

clazz.isAssignableFrom(Foo.class) will be true whenever the class represented by the clazz object is a superclass or superinterface of Foo.

clazz.isInstance(obj) will be true whenever the object obj is an instance of the class clazz.

That is:

clazz.isAssignableFrom(obj.getClass()) == clazz.isInstance(obj)

is always true so long as clazz and obj are nonnull.