FunctionExample.java

package com.learn.functionalInterfaces;

import java.util.function.Function;

public class FunctionExample {

 static Function<String, String> function1 = (str) -> str.toUpperCase();
 static Function<String, String> function2 = (str) -> str.concat(" default");

 public static void main(String[] args) {

 System.out.println(performConcat("test"));

 System.out.println(function1.andThen(function2).apply("test"));

 /**
 * Here function2 is performed first and it's result is passed to function1.
 */
 System.out.println(function1.compose(function2).apply("test"));


 }

 public static String performConcat(String str) {
 return function2.apply(str);
 }

}