There are seven feature which should be present in a language to classify it as a Pure Object Oriented Language. These are
- Encapsulation/Data Hiding
- All predefined types are objects
- All operations are performed by sending messages to objects
- All user defined types are objects.
Java Supports Primitive datatype such as int, byte, long… etc, to be used, which are not objects. So on this ground this does not qualify to be pure Object Oriented Language.