Question 1: Does Java supports pointers ? If yes then how? If no then why?
Java does not support pointers as is supported in, for example, C++ Because pointers are unsafe. Java uses reference types to hide pointers and programmers feel easier to deal with reference types without pointers. Type safety and security can no longer be guaranteed because the garbage collector may relocate referenced objects, invalidating such pointers if arbitrary manipulation of pointers is allowed.
Question 2: Is Java is fully Object-Oriented Language ? If yes,then what about int,float datatypes and what about multiple inheritance?
Java is an Object Oriented language but does not support operator overloading and multiple inheritance. You can use multiple interface inheritance to get some of the benefits of multiple inheritnace. The definition of fully Object Ointed language is subjective and is a matter of opinion. I don't think operator overloading and multiple inheritance are strict requirements for an OO language.
Object oriented theorists define three fundamental aspects of an object oriented language: encapsulation, inheritance and polymorphism. Java supports all three.
Question 3: J2EE is superset of J2ME or J2ME is superset of J2EE ?
I have not used J2ME myself so I will leave this question to fellow ranchers to answer. My simplified understanding is that:
J2ME is a subset of J2SE and J2EE is a superrset of J2SE