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Wiki MarkupThe Java compiler type-checks the arguments to each varargs method to ensure that the arguments are of the same type or object reference. However, the compile-time checking is ineffective when {{Object}} or generic {{T}} parameter types are used \ [[Bloch 2008|AA. References#Bloch 08]\]. Another requirement for providing strong compile-time type checking of variable argument methods is to be as specific as possible when declaring the type of the method parameter.

Noncompliant Code Example (Object)

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ReturnType method(SpecificObjectType... args) { }

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Retrofitting old methods containing final array parameters with generically typed varargs is not always a good idea. For example, given a method that does not accept an argument of a particular type, it could be possible to override the compile-time checking --- — through the use of generic varargs parameters --- — so that the method would compile cleanly rather than correctly, causing a compile-time error \[ [Bloch 2008|AA. References#Bloch 08]\].

Also, note that autoboxing does not allow strong compile-time type checking of primitive types and their corresponding wrapper classes.

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Automated detection appears to be straightforward.

Bibliography

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DCL52-J. Avoid ambiguous overloading of varargs methods      01. Declarations and Initialization (DCL)      DCL57-J. Do not derive a value associated with an enum from its ordinal