The Access To Foreign Data (ATFD) is the number of attributes from unrelated classes that are accessed directly or by invoking accessor methods. High ATFD is usually associated with low cohesion and high coupling.
Default Threshold2
Example:
ATFD is 2 for below class.
private static class KeySelector3 implements KeySelector<tuple3<integer, long,="" string="">, Tuple2<integer, long="">> { private static final long serialVersionUID = 1L; @Override public Tuple2<integer, long=""> getKey(Tuple3<integer, long,="" string=""> t) { return new Tuple2<>(t.f0, t.f1); } }</integer,></integer,></integer,></tuple3<integer,>