Exploring the New Features of Java 24: What Developers Need to Know

Java continues to evolve as one of the most dominant programming languages in the software development ecosystem. With the release of Java 24, Oracle and the OpenJDK community have once again delivered a robust set of enhancements, language improvements, and tooling updates that aim to improve developer productivity, runtime performance, and code maintainability. In this detailed guide, we’ll explore the new features of Java 24, how they impact modern Java development, and why this release matters for both enterprise and individual developers.

Overview of Java 24
Key Language Enhancements
JVM and Performance Improvements
API Updates and Library Additions
Project Panama and Foreign Function Interface Enhancements
Enhanced Pattern Matching
Improvements in Virtual Threads (Project Loom)
Deprecations and Removals
Tooling Updates and Build Enhancements
Migration Guide and Backward Compatibility
Why You Should Upgrade to Java 24
Final Thoughts

1. Overview of Java 24

Released as part of the six-month cadence, Java 24 (JDK 24) follows in the footsteps of Java 23 with incremental yet impactful improvements. This release continues the tradition of incubating and previewing major features while delivering stable enhancements to the Java Virtual Machine (JVM), core libraries, and language constructs.

With growing emphasis on performance, developer ergonomics, and foreign memory access, Java 24 is designed to meet the evolving needs of cloud-native applications, microservices, and high-throughput systems.

2. Key Language Enhancements

a. Record Patterns (Second Preview)

Record patterns simplify deconstruction of record values in instanceof checks and switch expressions. Building upon previous previews, Java 24 enhances type inference and syntax clarity.

if (obj instanceof Point(int x, int y)) {
    System.out.println("X: " + x + ", Y: " + y);
}

This makes code more concise and readable, especially in pattern-heavy logic such as AST manipulation or protocol handling.

b. Unnamed Variables and Patterns (Preview)

Java 24 introduces unnamed variables (_) to explicitly ignore values in pattern matching.

if (obj instanceof Point(_, int y)) {
    System.out.println("Only care about Y: " + y);
}

This improves intent clarity and reduces boilerplate.

3. JVM and Performance Improvements

a. Improved Garbage Collection

The G1 and ZGC collectors received notable improvements in heap compaction and concurrent region scanning, minimizing pause times and improving responsiveness in memory-intensive workloads.

b. Class-Data Sharing (CDS) Enhancements

CDS now supports dynamic archiving for more use cases, including containerized environments, reducing startup time by reusing metadata across JVM invocations.

c. Vector API (Sixth Incubator)

The Vector API continues to evolve, enabling developers to write performance-critical algorithms that compile down to SIMD instructions.

var a = IntVector.fromArray(IntVector.SPECIES_256, new int[]{1, 2, 3, 4}, 0);

This allows more control over low-level performance in compute-intensive applications like ML, gaming, and graphics.

4. API Updates and Library Additions

Java 24 brings a host of improvements to the standard library:

New StringTemplate API (Preview): Allows for template-based string construction with embedded expressions. This is a step toward safer, more powerful templating in Java.

String name = "Atinder";
StringTemplate st = STR."Hello, \{name}!";

Better Optional Handling: New utility methods like ifPresentOrElseThrow() provide fluent APIs for null safety.
Enhanced Collections: Improvements in Map, Set, and stream collectors further boost data handling capabilities.

5. Project Panama and Foreign Function Interface Enhancements

One of the most groundbreaking areas of progress in Java 24 is in Project Panama, which aims to simplify interoperability between Java and native code.

a. Foreign Function & Memory API (Third Preview)

Java 24 refines the FFM API with better memory segment safety, layout introspection, and function invocation capabilities.

try (MemorySegment segment = MemorySegment.allocateNative(100, arena)) {
    // interact with C-native structures
}

This significantly improves use cases in data science, image processing, and legacy integration.

6. Enhanced Pattern Matching

Java 24 continues to unify and streamline pattern matching with enhancements to switch expressions, sealed types, and record deconstruction.

Pattern Matching for switch: Now supports sealed type hierarchies and guarded patterns.

switch (shape) {
    case Circle c -> drawCircle(c);
    case Rectangle r when r.isSquare() -> drawSquare(r);
    default -> handleUnknown(shape);
}

This results in fewer if-else chains and cleaner type-safe branching.

7. Improvements in Virtual Threads (Project Loom)

Project Loom continues to redefine Java concurrency by allowing millions of lightweight threads to run with minimal footprint.

a. Virtual Threads Now Stable

Virtual threads are now out of preview, allowing developers to use them in production for high-concurrency applications without complex CompletableFuture or reactive code.

Thread.startVirtualThread(() -> {
    fetchUserData();
});

This drastically simplifies server code and parallel processing logic.

8. Deprecations and Removals

Java 24 also cleans up legacy APIs and prepares for future transitions:

Deprecated: Obsolete JMX and RMI-related APIs.
Removed: Legacy SecurityManager components.
Deprecated: Thread.stop() and related unsafe threading constructs.

Developers should audit their codebases to align with modern, secure alternatives.

9. Tooling Updates and Build Enhancements

a. Javac Diagnostics

Java 24’s javac introduces improved error messages and actionable diagnostics.

b. JShell Enhancements

JShell now supports better scripting and multivariable templates.

c. JLink & JDeps Improvements

Tools like jlink and jdeps get performance and usability enhancements for creating optimized custom runtimes.

10. Migration Guide and Backward Compatibility

Java 24 maintains excellent backward compatibility with previous LTS versions like Java 17 and Java 21. However, developers upgrading from Java 8 or Java 11 should test code against deprecated APIs and switch expressions.

Migration steps:

Run jdeps to check dependencies.
Enable preview features with --enable-preview during transition.
Adopt modularization where possible.

11. Why You Should Upgrade to Java 24

a. Boosted Developer Productivity

Features like virtual threads, record patterns, and unnamed variables result in less boilerplate and cleaner logic.

b. Improved Performance

From garbage collection to native interop, Java 24 is designed for the demands of modern cloud and edge computing.

c. Future-Ready Language Constructs

With a focus on pattern matching, structured concurrency, and templated strings, Java is embracing functional and declarative styles without compromising its object-oriented roots.

d. Security and Maintainability

By deprecating outdated constructs, Java 24 nudges teams toward safer and more maintainable code.

12. Final Thoughts

Java 24 exemplifies the balance between innovation and stability. Whether you’re building microservices, data pipelines, or desktop tools, this version empowers developers to write expressive, scalable, and maintainable code.

With features like Virtual Threads, Record Patterns, and Foreign Memory APIs maturing rapidly, Java is not only staying relevant but also leading the evolution of modern software engineering. If you’re still on older versions, now is the time to plan your migration and unlock the full potential of what Java 24 has to offer.

Stay tuned, adopt early, and code smarter. Java’s future is brighter than ever!