java-tutorials/libraries-6/src/main/java/com/baeldung/fj/FunctionalJavaMain.java
2020-04-29 20:49:15 +02:00

49 lines
1.5 KiB
Java

package com.baeldung.fj;
import fj.F;
import fj.Show;
import fj.data.Array;
import fj.data.List;
import fj.data.Option;
import fj.function.Characters;
import fj.function.Integers;
public class FunctionalJavaMain {
public static final F<Integer, Boolean> isEven = i -> i % 2 == 0;
public static void main(String[] args) {
List<Integer> fList = List.list(3, 4, 5, 6);
List<Boolean> evenList = fList.map(isEven);
Show.listShow(Show.booleanShow).println(evenList);
fList = fList.map(i -> i + 1);
Show.listShow(Show.intShow).println(fList);
Array<Integer> a = Array.array(17, 44, 67, 2, 22, 80, 1, 27);
Array<Integer> b = a.filter(Integers.even);
Show.arrayShow(Show.intShow).println(b);
Array<String> array = Array.array("Welcome", "To", "baeldung");
Boolean isExist = array.exists(s -> List.fromString(s).forall(Characters.isLowerCase));
System.out.println(isExist);
Array<Integer> intArray = Array.array(17, 44, 67, 2, 22, 80, 1, 27);
int sum = intArray.foldLeft(Integers.add, 0);
System.out.println(sum);
Option<Integer> n1 = Option.some(1);
Option<Integer> n2 = Option.some(2);
F<Integer, Option<Integer>> f1 = i -> i % 2 == 0 ? Option.some(i + 100) : Option.none();
Option<Integer> result1 = n1.bind(f1);
Option<Integer> result2 = n2.bind(f1);
Show.optionShow(Show.intShow).println(result1);
Show.optionShow(Show.intShow).println(result2);
}
}