Java Programming by Pearson

Packages and Interfaces • 253

to, in terms of the type signature of the methods. The class that implements the interface provides an

implementation for each method, just as with an abstract method in an abstract class.

So, an interface can be considered as an abstract class with all abstract methods. The interface itself can

have either public, package, private or protected access defi ned. All methods declared in an

interface are implicitly abstract and implicitly public . It is not necessary and in fact considered redundant to

declare a method in an interface to be an abstract. Data can be defi ned in an interface, but it does not happen ...