Microsoft for Java Developers
News, updates, and insights for Java development with Microsoft tools, Azure services, and OpenJDK.
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Java OpenJDK October 2025 Patch & Security Update
Hello Java customers! We are happy to announce the latest July 2025 patch & security update release for the Microsoft Build of OpenJDK. Download and inst...
Latest posts
Java at Microsoft: 2025 Year in Review
A breakthrough year for modernization, AI‑assisted development, Agentic AI development, and platform innovation 2025 was one of the most significant years yet for Java at Microsoft. From the arrival of OpenJDK 25 as the newest Long‑Term Support (LTS) release, to AI‑powered modernization workflows with GitHub Copilot app modernization, to Agentic AI development in Microsoft AI Foundry with Java frameworks like LangChain4j, Spring AI, Quarkus AI, and Embabel, with major Visual Studio Code and Azure platform investments. Microsoft deepened its commitment across the entire Java ecosystem. Java 25: A New LTS Era B...
Beyond Ergonomics: How the Azure Command Launcher for Java Improves GC Stability and Throughput on Azure VMs
In our previous blog we introduced Azure Command Launcher for Java () —a safe, resource-aware way to launch the JVM without hand-tuning dozens of flags. This follow-up shares performance results, focusing on how affects G1 behavior, heap dynamics, and pause characteristics under a long-running, allocation-intensive workload: SPECjbb 2015 (JBB). Test bed: 4-vCPU, 16-GB Azure Linux/Arm64 VM running the Microsoft Build of OpenJDK. JDKs exercised: Validated on JDK 17 (17.0.17), 21 (21.0.9), and 25 (25.0.1); all figures in this post are from the JDK 17 runs. Trends on 21/25 matched the 17 results. How we ran...
From Complexity to Simplicity: Intelligent JVM Optimizations on Azure
Introduction As cloud-native architectures scale across thousands of containers and virtual machines, Java performance tuning has become more distributed, complex, and error-prone than ever. As highlighted in our public preview announcement, traditional JVM optimization relied on expert, centralized operator teams manually tuning flags and heap sizes for large application servers. This approach simply doesn’t scale in today’s highly dynamic environments, where dozens—or even hundreds—of teams deploy cloud-native JVM workloads across diverse infrastructure. To address this, Microsoft built Azure Command Launch...
Announcing the Public Preview of Azure Command Launcher for Java
Today we are announcing the Public Preview of the Azure Command Launcher for Java, a new tool that helps developers, SREs, and infrastructure teams standardize and automate JVM configuration on Azure. The goal is to simplify tuning practices and reduce resource waste across Java workloads. JVM Tuning in a Cloud-Native World Before the rise of microservices, Java applications were typically deployed as Java EE artifacts (WARs or EARs) on managed application servers. Ops teams were responsible for configuring and tuning the JVM, often on powerful servers that hosted multiple applications on a single Java EE app...
Introducing Major New Agentic Capabilities for GitHub Copilot in JetBrains and Eclipse
GitHub Copilot is taking a major step forward with expanded, deeply integrated support for JetBrains and Eclipse — bringing a new generation of agentic, intelligent capabilities directly into your favorite Java IDEs. This release strengthens Copilot’s cross-IDE experience, unifies agentic workflows, and unlocks more powerful automation to help developers code faster, modernize confidently, and stay in flow. New Agentic Capabilities This is the year of the agents. Developers need more control than ever—both in how they work with agents and how agents adapt to their workflows. After introducing Custom Agents in ...
JDConf 2026 Is Coming With Modern Solutions for an Agentic World
Technology is accelerating faster than ever, and developers are once again at the helm, shaping the future of applications, intelligence, and enterprise systems. With the rise of large language models (LLMs), agent-oriented architectures, and AI-driven development paradigms, Java developers find themselves in a uniquely powerful position to modernize code already powering critical systems, and to build the software of tomorrow. Java remains one of the world’s most trusted languages for enterprise, cloud, mobile and mission-critical systems. As James Governor, from developer analyst firm RedMonk, recently...
Java OpenJDK October 2025 Patch & Security Update
Hello Java customers! We are happy to announce the latest July 2025 patch & security update release for the Microsoft Build of OpenJDK. Download and install the binaries today. Check our release notes page for details on fixes and enhancements. The source code of our builds is available now on GitHub for further inspection: jdk25u, jdk21u, jdk17u, jdk11u. Microsoft Build of OpenJDK specific updates OpenJDK25 OpenJDK21 OpenJDK17 OpenJDK11 Summary of Upstream Updates OpenJDK 25 OpenJDK 21 OpenJDK 17 OpenJDK 11 ...
MCP Registry and Allowlist Controls for Copilot in JetBrains and Eclipse Now in Public Preview
MCP registry and allowlist controls for GitHub Copilot in JetBrains IDEs and Eclipse are now available in public preview in nightly/pre-release builds. What’s new MCP Registry An MCP Registry is a directory of Model Context Protocol (MCP) servers. For users of JetBrains IDEs and Eclipse, you can now configure your MCP Registry and browse available MCP servers directly within your IDE. This greatly streamlines setup and provides a seamless experience for discovering and managing MCP servers right from the editor. Allow List Controls As an enterprise or organization owner, you can configure an MCP Registry...
Java and AI for Beginners: a practical video series for Java
If you're looking for a clear, no-nonsense path into generative AI on Java, this series is for you. Microsoft's Java and AI for Beginners video series is a set of short tutorials that introduce the concepts, tooling, and patterns you need to get started at a pace that respects your time and experience. What the series covers We help you through foundational ideas first and then move into hands-on examples: Each video is short and focused. Watch them in order if you are new to the space, or skip into the topics that match your immediate needs. Integrations you w...
Microsoft’s OpenJDK builds now ready for Java 25
We’re excited to announce that the Microsoft Build of OpenJDK binaries are now available for Java 25. As always, our builds aim to provide a high-quality, production-ready build of OpenJDK, with binaries tested across platforms (Windows, Linux, macOS) and backed by our support and release pipelines. With this release, we invite developers, teams, and organizations to start migrating to Java 25, and in doing so, to take advantage of the many enhancements that have accumulated since Microsoft Build of OpenJDK 21 (our previous LTS release). Microsoft Build of OpenJDK 25 is fully supported for deployment on Azure ...
Unlocking MCP in JetBrains: How Copilot Uses Sampling, Prompts, Resources, and Elicitation
With the enhanced capability of the MCP on JetBrains, you can now bring prompts, resources, and even interactive tools directly into your IDE interacting with MCP. This means more flexible workflows, deeper context, and smoother collaboration between Copilot and your coding environment. Let’s take a look at what you can do today with MCP Sampling, Prompts, Resources, and Elicitation. Prerequisites To easily enable everything, you can copy and paste these settings into your `mcp.json` file: MCP Sampling – Fine-Tune How Copilot Responds With MCP Sampling, you can...
Building a Runtime JAR inspector in 10 hours
Last Friday I was reviewing our backlog items in the Java Engineering Group, and found an idea we had when Log4Shell happened. To this day, there is still no main stream solution to "find in production where a given JAR is being used". Why runtime truth matters (Log4Shell) When Log4Shell hit, lots of teams hunted for log4j through source control and CI pipelines. Helpful, but incomplete. Two realities get in the way: Finding where a vulnerable artifact is present in production, at runtime, and whether is being used, is far more important than monitoring source code and build pipelines. We s...
“HTTP header exceeding 8,192 bytes” error when using the Azure SDK for Java
A recent issue was identified in the azure-resourcemanager libraries for Java regarding HTTP headers exceeding 8,192 bytes. Following analysis, this was addressed within the Azure SDK for Java by increasing the maximum response header size limit of “reactor-netty-http” to 256 KB, accommodating larger headers. To benefit from this mitigation, it is necessary to upgrade azure-core-http-netty to version 1.15.12 or later. Alternatively, if you are utilizing the BOM, please use version 1.2.36 or above. This issue originated from an update in Azure Resource Manager to add a cryptographic token to long-running-operat...
Generative AI for Beginners – Java Edition launched
IN ONE hour, all ONLINE, complete our new training for Generative AI for Beginners – Java Edition - part of the incredible Microsoft Generative AI series - Python, .NET and JavaScript. In this training get first-hand experience with Core Generative AI Techniques and Tools we’re using inside Microsoft: Quick Start 📅Book now and Learn LIVE with FREE Training! 👉 Generative AI for Beginners - Java Edition | Microsoft Reactor
Java OpenJDK July 2025 Patch & Security Update
Hello Java customers! We are happy to announce the latest July 2025 patch & security update release for the Microsoft Build of OpenJDK. Download and install the binaries today. Check our release notes page for details on fixes and enhancements. The source code of our builds is available now on GitHub for further inspection: jdk21u, jdk17u, jdk11u. Microsoft Build of OpenJDK specific updates OpenJDK21 OpenJDK17 OpenJDK11 Summary of Upstream Updates OpenJDK 21 OpenJDK 17 OpenJD...
Microsoft and LangChain4j: A Partnership for Secure, Enterprise-Grade Java AI Applications
The artificial intelligence landscape presents unprecedented opportunities for Java developers. With decades of experience building robust enterprise applications using Spring, Quarkus and Jakarta EE, Java developers are uniquely positioned to create sophisticated AI solutions. The emergence of specialized AI libraries like LangChain4j enables them to leverage their existing expertise while building secure, scalable, and maintainable AI applications. Introducing LangChain4j: A Comprehensive Java AI Library LangChain4j represents a significant advancement in Java-based AI development. This community-driven l...
Customize GitHub Copilot in JetBrains with Custom Instructions
Today, you can use Custom Instructions in JetBrains to speed up development while staying aligned with your team's coding standards and personal preferences. Whether you're working on a solo project or part of a larger team, adhering to consistent coding standards is essential. Custom Instructions provide a mechanism to reinforce team coding guidelines or embed personal coding preferences. Example: Make custom instructions for newly generated code Make sure you have the latest version of GitHub Copilot installed on you JetBrains IDE. Then, navigate to the GitHub Copilot settings to find the Custom Inst...
What’s New for Java Developers in Azure Cosmos DB (NoSQL)?
The Java ecosystem around Azure Cosmos DB has quietly grown a lot stronger in the first half of 2024. And the updates are especially exciting if you’re working on scalable apps or exploring GenAI workloads. From new support for vector search and indexing, to better throughput management and improved integrations with Apache Kafka, Spring Data, and Apache Spark, there’s a lot to unpack. If you’re building Java apps with Cosmos DB or just curious about how far the NoSQL SDK has come, you’ll want to check out this update. 👉 Continue reading: Latest NoSQL Java Ecosystem Updates (June 2024 – June 2025)