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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.
Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.
Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.
With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.
Try a 14-Day Free Trial of Orkes Conductor today.
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:
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:
Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.
Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.
With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.
Try a 14-Day Free Trial of Orkes Conductor today.
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.
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1. Overview
In this tutorial, we’re going to have a look at some ways of validating UUID (Universally Unique Identifier) strings in Java.
We’ll go through one of the UUID class methods, and then we’ll use regular expressions.
2. Using UUID.fromString()
One of the quickest ways of checking if a String is a UUID is by trying to map it using the static method fromString belonging to the UUID class. Let’s try it out:
@Test
public void whenValidUUIDStringIsValidated_thenValidationSucceeds() {
String validUUID = "26929514-237c-11ed-861d-0242ac120002";
Assertions.assertEquals(UUID.fromString(validUUID).toString(), validUUID);
String invalidUUID = "invalid-uuid";
Assertions.assertThrows(IllegalArgumentException.class, () -> UUID.fromString(invalidUUID));
}In the above code snippet, we can see that in case the string we’re trying to validate doesn’t represent a UUID, then an IllegalArgumentException will be thrown. However, the method fromString will return `00000001-0001-0001-0001-000000000001` for strings such as `1-1-1-1-1`. So we have included the string comparison to take care of this case.
Some might argue that using exceptions is not a good practice for flow control, so we’re going to see a different way of achieving the same result.
3. Using Regular Expressions
Another way of validating a UUID is to use a regular expression that will match exactly the format.
Firstly, we need to define a Pattern that will be used to match the string.
Pattern UUID_REGEX =
Pattern.compile("^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$");Then, we can use this pattern to try matching it to a string in order to validate whether or not it is a UUID:
@Test
public void whenUUIDIsValidatedUsingRegex_thenValidationSucceeds() {
Pattern UUID_REGEX =
Pattern.compile("^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$");
Assertions.assertTrue(UUID_REGEX.matcher("26929514-237c-11ed-861d-0242ac120002").matches());
Assertions.assertFalse(UUID_REGEX.matcher("invalid-uuid").matches());
}4. Conclusion
In this article, we’ve learned how to validate a UUID string by using regular expressions or by taking advantage of the static method of the UUID class.
The code backing this article is available on GitHub. Once you're logged in as a Baeldung Pro Member, start learning and coding on the project.
