@Documented @Retention(value=RUNTIME) @Target(value={CONSTRUCTOR,METHOD}) public @interface SafeVarargs
In addition to the usage restrictions imposed by its @Target meta-annotation, compilers are required to implement
additional usage restrictions on this annotation type; it is a
compile-time error if a method or constructor declaration is
annotated with a @SafeVarargs annotation, and either:
static nor final.
Compilers are encouraged to issue warnings when this annotation type is applied to a method or constructor declaration where:
Object, and String.
(The unchecked warnings this annotation type suppresses already do
not occur for a reifiable element type.)
@SafeVarargs // Not actually safe!
static void m(List<String>... stringLists) {
Object[] array = stringLists;
List<Integer> tmpList = Arrays.asList(42);
array[0] = tmpList; // Semantically invalid, but compiles without warnings
String s = stringLists[0].get(0); // Oh no, ClassCastException at runtime!
}
leads to a ClassCastException at runtime.
Future versions of the platform may mandate compiler errors for such unsafe operations.
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