import java.util.List; class Temp<K> { public static List<String> foo() { return parallelizePairs(asList(new Tuple())).partitionBy(); } public static <T> List<T> asList(T a) { return null; } public static <K> Temp<K> parallelizePairs(List<Tuple<K>> list) { return null; } public List<K> partitionBy() { return null; } } class Tuple<A> { public Tuple() {} }