Curry3.java

public class Curry3 {
  
public static <A, B, C, X> Function<A, Function<B, Function<C, X>>> curry3(TriFunction<A, B, C, X> f) {
    return a -> b -> c -> f.apply(a, b, c);
}

public static <A, B, C, X> TriFunction<A, B, C, X> unCurry3(Function<A, Function<B, Function<C, X>>> f) {
    return (a, b, c) -> f.apply(a).apply(b).apply(c);
}
 
  //example
  public static void main(String[] args) {
        TriFunction<Integer, Integer, Integer, Integer> xx = (a, b, c) -> a + b + c;
        xx.apply(1,2,3); //6
        curry3(xx).apply(1).apply(2).apply(3); //6
        uncurry3(curry3(add)).apply(1,2,3); //6
    }
}

@FunctionalInterface
interface TriFunction<A, B, C, X> {
    X apply (A a, B b, C c);
}