Functional supplier interface in Java tutorial There are only half a dozen classes you really need to master to become competent in the world of functional programming. The java.util.function package ...

See the Java 101 Java interfaces tutorial for a more in-depth introduction to using interfaces in your Java programs, including where and where not to use default, static, and private methods.

For example, when the user presses a key, the MIDP runtime calls the Canvas.keyPressed() method and passes the key code. By default, the keyPressed() method does nothing.