Functional Interfaces in Java | Functional Programming in Java #2

Опубликовано: 04 Апрель 2026
на канале: Jonas Keil
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Functional interfaces form the basis of functional programming in Java. In this video, I'll show you everything you need to know about them.

Link to the documentation: https://docs.oracle.com/javase/8/docs...

0:00 Introduction
0:06 Functional Interfaces: Introduction
1:00 What are Functional Interfaces?

3:50 Functional Interface Documentation
4:28 1. Function Interface
8:26 Chaining Functions
10:27 2. Consumer Interface
14:14 3. Predicate Interface
17:37 4. Supplier Interface
18:57 Understanding All Functional Interfaces
20:52 Info

📚You might also be interested in:

Streams in Java: [still in production]
Lambdas in Java:

Threads in Java:

Functional interfaces allow you to store the logic of methods in objects. The trick is knowing when to use which interface. The most commonly used interfaces are: Consumer, Function, Predicate, and Supplier.

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Functional interfaces can seem complicated at first... but you'll definitely understand them! :) My respect to you for participating alongside the #Tutorial and attempting the challenges! That will really help you internalize functional interfaces in Java!

Let me know in the comments if this video helped you better understand functional interfaces!


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Are you a student or pupil and want to learn Java, but don't know where to start? Then you've come to the right place!

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#Programming #Java

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