A programmer assertion that the body of the annotated method orconstructor does not perform potentially unsafe operations on itsvarargs parameter. Applying this annotation to a method orconstructor suppresses unchecked warnings about anon-reifiable variable arity (vararg) type and suppressesunchecked warnings about parameterized array creation at callsites.

In addition to the usage restrictions imposed by its@Target meta-annotation, compilers are required to implementadditional usage restrictions on this annotation type; it is acompile-time error if a method or constructor declaration isannotated with a@SafeVarargs annotation, and either:

• the declaration is a fixed arity method or constructor
• the declaration is a variable arity method that is neitherstatic norfinal norprivate.

Compilers are encouraged to issue warnings when this annotationtype is applied to a method or constructor declaration where:

• The variable arity parameter has a reifiable element type,which includes primitive types,Object, andString.(The unchecked warnings this annotation type suppresses already donot occur for a reifiable element type.)
• The body of the method or constructor declaration performspotentially unsafe operations, such as an assignment to an elementof the variable arity parameter's array that generates an uncheckedwarning. Some unsafe operations do not trigger an uncheckedwarning. For example, the aliasing in

  @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 aClassCastException at runtime.

  Future versions of the platform may mandate compiler errors forsuch unsafe operations.