Java 8 Features – Complete Tutorial

Java 8 is the most awaited release of Java programming language development because, in the entire history of Java, it never released that many major features. It consists of major features of Java. It is a new version of Java and was released by Oracle on 18 March 2014. Java provided support for functional programming, new Java 8 APIs, a new JavaScript engine, new Java 8 streaming API, functional interfaces, default methods, date-time API changes, etc.

Major Java 8 Features Introduced

There are a few major Java 8 features mentioned below:

• Lambda Expressions: Concise functional code using ->.
• Functional Interfaces: Single-method interfaces.
• Introduced and Improved APIs:
  1. Stream API: Efficient Data Manipulation.
  2. Date/Time API: Robust Date and Time Handling.
  3. Collection API Improvements: Enhanced Methods for Collections (e.g., removeIf, replaceAll).
  4. Concurrency API Improvements: New classes for parallel processing (e.g., CompletableFuture).
• Optional Class: Handle null values safely.
• forEach() Method in Iterable Interface: Executes an action for each element in a Collection.
• Default Methods: Evolve interfaces without breaking compatibility.
• Static Methods: Allows adding methods with default implementations to interfaces.
• Method References: Refer to methods easily.

This Java 8 tutorial covers all the important Java 8 features like Java 8 APIs, Java arrays, Java 8 ArrayList, and many more included in the Java 8 programming language. To explore detail features of Java language you can explore Java course, in this course you will get a free full beginner to advanced topics of Java programming.

Java 8 Features

• Lambda Expressions
• Functional Interfaces
• Method Reference
• Streams
• Comparable and Comparator
• Optional Class
• Date/Time API
• Miscellaneous

Lambda Expressions

Lambda Expression basically expresses an instance of the functional interface, in other words, you can say it provides a clear and concise way to represent a method of the functional interface using an expression. Lambda Expressions are added in Java 8.

• Lambda Expressions in Java 8
• Lambda Expressions Parameters
• Java Lambda Expression with Collections
• Lambda Expression Variable Capturing with Examples
• How to Create Thread using Lambda Expressions in Java?
• Serialization of Lambda Expression in Java
• Block Lambda Expressions in Java
• Match Lambdas to Interfaces in Java
• Converting ArrayList to HashMap in Java 8 using a Lambda Expression
• Check if a String Contains Only Alphabets in Java Using Lambda Expression
• Remove Elements From a List that Satisfy a Given Predicate in Java

Functional Interfaces

An interface that contains only one abstract method is known as a functional interface, but there is no restriction, you can have n number of default and static methods inside a functional interface.

• Functional Interfaces in Java
• Consumer Interface in Java with Examples
• BiConsumer Interface in Java with Examples
• Predicate Interface with Examples
• Function Interface in Java with Examples
• Supplier Interface in Java with Examples

Method Reference

Method reference is a shorthand notation of a lambda expression to call a method. There are four types of method references that are as follows:

• Static Method Reference
• Instance Method Reference of a particular object
• Instance Method Reference of an arbitrary object of a particular type
• Constructor Reference.

Example:

numList.stream().filter(n -> n > 5).sorted().forEach(System.out::println);

• Method References in Java with examples
• Converting ArrayList to HashMap using Method Reference in Java 8

Streams