Navigating the Flow: A Deeper Dive into Consumer, Predicate, and Supplier Interfaces in Java Streams

Introduction

In the vast landscape of Java programming, the concept of streams has emerged as a powerful tool for working with sequences of elements. Whether you’re crunching numbers, manipulating data, or processing files, streams provide an elegant and efficient way to handle collections. Central to this process are three key interfaces: Consumer, Predicate, and Supplier. In this article, we’ll embark on a journey to explore these interfaces and understand how they play pivotal roles in the world of Java streams.

Consumer Interface: Savoring the Elements

Imagine you’re at a buffet, and your task is to taste each dish and give your opinion. In the world of Java streams, the Consumer interface takes on a similar role. It doesn’t return any value; rather, it “consumes” the elements of a stream one by one.

The Consumer interface embodies the “do something” philosophy. It represents an operation that accepts a single input argument and performs a specified action on it. This action could involve printing elements, updating values, or executing any custom logic.

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

public class ConsumerExample {
    public static void main(String[] args) {
        List<String> fruits = List.of("Apple", "Banana", "Orange", "Mango");

        // Creating a Consumer to print each fruit…