JAVA

functionality of consumer functional interface in java

package com.zetcode;

import java.util.ArrayList;
import java.util.List;
import java.util.function.Consumer;

public class ConsumerEx4 {

    public static void main(String[] args) {

        var vals = new ArrayList<Integer>();
        vals.add(2);
        vals.add(4);
        vals.add(6);
        vals.add(8);

        Consumer<List<Integer>> addTwo = list -> {

            for (int i = 0; i < list.size(); i++) {

                list.set(i, 2 + list.get(i));
            }
        };

        Consumer<List<Integer>> showList = list -> 
            list.forEach(System.out::println);

        addTwo.andThen(showList).accept(vals);
    }
}

functionality of consumer functional interface in java

@FunctionalInterface
public interface Consumer<T> {
    void accept(T t);
}

functionality of consumer functional interface in java

package com.zetcode;

import java.util.function.Consumer;
import java.util.function.IntConsumer;

public class ConsumerEx2 {

    public static void main(String[] args) {

        Consumer<Integer> printMultiplyBy100 = (val) -> System.out.println(val * 100);

        printMultiplyBy100.accept(3);
        printMultiplyBy100.accept(4);
        printMultiplyBy100.accept(5);

        IntConsumer printMultiplyBy500 = a -> System.out.println(a * 50);
        printMultiplyBy500.accept(1);
        printMultiplyBy500.accept(2);
        printMultiplyBy500.accept(3);
    }
}

functionality of consumer functional interface in java

package com.zetcode;

import java.util.List;
import java.util.function.Consumer;

public class ConsumerEx3 {

    public static void main(String[] args) {

        var words = List.of("falcon", "wood", "rock", "forest",
                "river", "water");

        words.forEach(new Consumer<String>() {
            @Override
            public void accept(String s) {

                System.out.println(s);
            }
        });
    }
}