Because Java permits only single inheritance, this restriction on abstract classes severely constrains their use as type definitions.Any class that defines all the required methods and obeys the ...

An interface is a completely "abstract class" that is used to group related methods with empty bodies. To access the interface methods, the interface must be "implemented" (kinda like inherited) by ...

Interface with default methods in java 8in later version of java interfaces always contained only method declaration. we are not giving method definition in the interfaces because java did not allow ...