Reports instantiations of java.util.Set objects whose content types are enumerated classes. Such Set objects can be replaced with java.util.EnumSet objects.

EnumSet implementations can be much more efficient compared to other sets, as the underlying data structure is a bit vector. Use the quick-fix to replace the initializer with a call to EnumSet.noneOf(). This quick-fix is not available when the type of the variable is a sub-class of Set.

Example:


  enum MyEnum { FOO, BAR; }

  Set<MyEnum> enums = new HashSet<MyEnum>();

After the quick-fix is applied:


  enum MyEnum { FOO, BAR; }

  Set<MyEnum> enums = EnumSet.noneOf(MyEnum.class);