Mocking is an essential part of unit testing, and the Mockito library makes it easy to write clean and intuitive unit tests for your Java code.
Get started with mocking and improve your application tests using our Mockito guide:
Handling concurrency in an application can be a tricky process with many potential pitfalls. A solid grasp of the fundamentals will go a long way to help minimize these issues.
Get started with understanding multi-threaded applications with our Java Concurrency guide:
Spring 5 added support for reactive programming with the Spring WebFlux module, which has been improved upon ever since. Get started with the Reactor project basics and reactive programming in Spring Boot:
Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.
But these can also be overused and fall into some common pitfalls.
To get a better understanding on how Streams work and how to combine them with other language features, check out our guide to Java Streams:
Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:
Yes, Spring Security can be complex, from the more advanced functionality within the Core to the deep OAuth support in the framework.
I built the security material as two full courses - Core and OAuth, to get practical with these more complex scenarios. We explore when and how to use each feature and code through it on the backing project.
You can explore the course here:
Spring Data JPA is a great way to handle the complexity of JPA with the powerful simplicity of Spring Boot.
Get started with Spring Data JPA through the guided reference course:
Refactor Java code safely — and automatically — with OpenRewrite.
Refactoring big codebases by hand is slow, risky, and easy to put off. That’s where OpenRewrite comes in. The open-source framework for large-scale, automated code transformations helps teams modernize safely and consistently.
Each month, the creators and maintainers of OpenRewrite at Moderne run live, hands-on training sessions — one for newcomers and one for experienced users. You’ll see how recipes work, how to apply them across projects, and how to modernize code with confidence.
Join the next session, bring your questions, and learn how to automate the kind of work that usually eats your sprint time.
1. Overview
In this short tutorial, we’ll compare the three different Java Editions. We’ll see what functionalities they provide and their typical use cases.
2. Java Standard Edition
Let’s start with the Java Standard Edition, or Java SE, for short. This edition provides the core functionalities of the Java language.
Java SE provides the essential components for Java applications: Java Virtual Machine, Java Runtime Environment, and Java Development Kit. As of writing this article, the latest version is Java 18.
Let’s describe a simple use case for a Java SE application. We can implement the business logic using OOP concepts, make HTTP requests using the java.net package, and connect to a database with JDBC. We can even display a user interface using Swing or AWT.
3. Java Enterprise Edition
Java EE is based on the Standard Edition and provides even more APIs. The abbreviation stands for Java Enterprise Edition, but it can be called Jakarta EE. They both refer to the same thing.
The new Java EE APIs allow us to create larger, scalable applications.
Generally, Java EE applications are deployed to an application server. Many web-related APIs are provided to facilitate this: WebSocket, JavaServer Pages, JAX-RS, etc. The enterprise features also include APIs related to JSON processing, security, Java Message Service, JavaMail, etc.
In a Java EE application, we can use everything from the standard APIs. On top of that, we can use more advanced technologies.
Now let’s see a use case for Java EE. For example, we can create servlets to process HTTP requests from users and create dynamic UI using JavaServer Pages. We can produce and consume messages using JMS, send emails and authenticate users to make our application secure. Furthermore, we can use the dependency injection mechanism to make our code more maintainable.
4. Java Micro Edition
Java Micro Edition or Java ME provides APIs for applications targeting embedded and mobile devices. These can be mobile phones, set-top boxes, sensors, printers, etc.
Java ME includes some Java SE functionalities while providing new APIs specific to these devices. For example, Bluetooth, location, sensor APIs, etc.
Most of the time, these small devices have resource constraints in terms of CPU or memory. We must consider these constraints when using Java ME.
Sometimes the target device might not even be available to us to test our code. The SDK can help with this because it provides emulators, application profiling, and monitoring.
For instance, a simple Java ME application could read a temperature sensor’s value and send it in an HTTP request along with its location.
5. Conclusion
In this short article, we got to know what the three Java Editions are, and we compared the functionalities that each of them provides.
Java SE can be used for simple applications. It’s the best starting point for learning Java. We can use Java EE to create more complex and robust applications. Finally, we can use Java ME if we would like to target embedded and mobile devices.
