I notice you have some C++ questions in your profile. If you understand the concept of multiple-inheritance from C++ (referring to classes that inherit characteristics from more than one other class), Java does not allow this, but it does have keyword interface
, which is sort of like a pure virtual class in C++. As mentioned by lots of people, you extend
a class (and you can only extend from one), and you implement
an interface -- but your class can implement as many interfaces as you like.
Ie, these keywords and the rules governing their use delineate the possibilities for multiple-inheritance in Java (you can only have one super class, but you can implement multiple interfaces).