Classes can implement any number of interfaces in their public section. The left-hand side of the diagram shows the declaration and implementation part of a local class C1, which implements several interfaces in its public section. The class must implement all of the interface methods in its implementation part.

The right-hand side illustrates the structure of the class with the components in their respective visibility areas, and the implementation of the methods. The interface components extend the public section of the class in which they are declared.