Package edu.pdx.cs410J.j2se15

Class CovariantReturns

java.lang.Object

edu.pdx.cs410J.j2se15.CovariantReturns

public class CovariantReturns
extends Object

This class demonstrates covariant returns in JDK 1.5. The Java compiler allows an overriding method to change the method's return type to be a subclass of the overriden method's return type. However, you have to be extra careful when using covariant returns with legacy code. If someone else overrides a method and doesn't change the return type, their code will not compile.

Since:

Winter 2004

Author:

David Whitlock

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	CovariantReturns.Animal	An animal that can be cloned.
(package private) static class	CovariantReturns.Human
(package private) static class	CovariantReturns.Student

Constructor Summary

Constructors

Constructor	Description
CovariantReturns()

Method Summary

Modifier and Type	Method	Description
static void	main(String[] args)	A main class that clones some animals.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

CovariantReturns

public CovariantReturns()

Method Details

main

public static void main(String[] args)

A main class that clones some animals. Note that we don't need to cast the result of the clone method.