Is java a pure object oriented language?

It isn't.
A language like Smalltalk may be called pure object oriented language.
Java has native data types like int, float, etc.
that are not objects themselves.
On the other hand Smalltalk does not have native types.
You would be surprised to know that in Smalltalk even the class is an object.
The way to instantiate a new object of the class is to call a method on the class object!

Yes we can say that it is pure object oriented from the prespective of wrapper classes but you still have primitives and they kept it for performance concerns.

Yes.
You dont need to use primitives.
Use Wrapper classes.

Yes. Java is a purely Object Oriented Language as the all the primitives are present in classes called Wrapper Classes.