android/guava/src/com/google/common/base/Predicates.java
@GwtCompatible(serializable = true)
  public static <T> Predicate<T> notNull() {
    return ObjectPredicate.NOT_NULL.withNarrowedType();
  }
@GwtCompatible(serializable = true)
  public static <T> Predicate<T> notNull() {
    return ObjectPredicate.NOT_NULL.withNarrowedType();
  }
Returns a predicate that evaluates to {@code true} if the object reference being tested is not
null.