The Java Language Specification, Third Edition

CLASSES Overloading 8.4.9
DISCUSSION
This can happen, if a superclass is parametric, and it has two methods that were distinct in
the generic declaration, but have the same signature in the particular invocation used.
Otherwise, there are two possible cases:
• If one of the inherited methods is not abstract, then there are two subcases:
◆ If the method that is not abstract is static, a compile-time error occurs.
◆ Otherwise, the method that is not abstract is considered to override, and
therefore to implement, all the other methods on behalf of the class that
inherits it. If the signature of the non-abstract method is not a subsignature
of each of the other inherited methods an unchecked warning must be
issued (unless suppressed (§9.6.1.5)). A compile-time error also occurs if
the return type of the non-abstract method is not return type substitutable
(§8.4.5) for each of the other inherited methods. If the return type of the
non-abstract method is not a subtype of the return type of any of the other
inherited methods, an unchecked warning must be issued. Moreover, a compile-time
error occurs if the inherited method that is not abstract has a
throws clause that conflicts (§8.4.6) with that of any other of the inherited
methods.
• If all the inherited methods are abstract, then the class is necessarily an
abstract class and is considered to inherit all the abstract methods. A
compile-time error occurs if, for any two such inherited methods, one of the
methods is not return type substitutable for the other (The throws clauses do
not cause errors in this case.)
DRAFT
There might be several paths by which the same method declaration might be
inherited from an interface. This fact causes no difficulty and never, of itself,
results in a compile-time error.
8.4.9 Overloading
If two methods of a class (whether both declared in the same class, or both inherited
by a class, or one declared and one inherited) have the same name but signatures
that are not override-equivalent, then the method name is said to be
overloaded. This fact causes no difficulty and never of itself results in a compile-
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