This week's Java roundup for September 7th, 2026, features news highlighting: new JEPs for ahead-of-time compilation and structured concurrency; GA releases of Jakarta CDI 5.0 and ADK for Kotlin 1.0; the September 2026 edition of Open Liberty; point releases of TornadoVM and RefactorFirst; a maintenance release of Micronaut; and first releases candidates of Groovy 6.0 and Gradle 9.8.
OpenJDK
JEP 544, Ahead-of-Time Code Compilation, has been elevated from its JEP Draft 8335368 to Candidate status. This JEP proposes to improve application startup and warmup time such that it is instantly available with optimized native code when the HotSpot JVM starts. This enables applications to achieve peak performance more quickly and to sustain peak performance.
JEP 543, Structured Concurrency, has been elevated from its JEP Draft 8389757 to Candidate status. This JEP proposes to finalize this feature, without change, after seven rounds of preview, delivered in JDK 21 through the upcoming release of JDK 27, and two rounds of incubator delivered in JDK 19 and JDK 20. This feature simplifies concurrent programming by introducing structured concurrency to "treat groups of related tasks running in different threads as a single unit of work, thereby streamlining error handling and cancellation, improving reliability, and enhancing observability."
JDK 27
Build 35 remains the current build in the JDK 27 early-access builds. Further details on this release may be found in the release notes.
JDK 27 will be released on Tuesday, September 15, 2026. InfoQ will follow up with a more detailed news story.
JDK 28
Build 15 of the JDK 28 early-access builds was made available this past week featuring updates from Build 14 that include fixes for various issues. More details on this release may be found in the release notes.
For JDK 28 and JDK 27, developers are encouraged to report bugs via the Java Bug Database.
TornadoVM
Approximately one week after the release of version 6.0, TornadoVM 6.1.0 delivers bug fixes and an improvements to the fixed cost the host pays per operation, namely: skip upload of the per-launch 24-byte kernel-argument kernel stack-frame when the contents are identical; and skip the stream synchronisation when nothing has been enqueued. Further details on this release may be found in the release notes. InfoQ will follow up with a more detailed news story on the release of version 6.0.0.
Jakarta EE
In his weekly Hashtag Jakarta EE blog, Ivar Grimstad, Jakarta EE Developer Advocate at the Eclipse Foundation, provided an update on Jakarta EE 12, writing:
Jakarta Contexts and Dependency Injection (CDI) 5.0 was approved by the Specification Committee this week as the first specification targeting Jakarta EE 12. This is an important milestone for Jakarta EE 12 as CDI is one of the most central specifications in the Platform. More specifications will follow soon.
The design of the Starter for Jakarta EE has been refreshed to align with the design of the Jakarta EE website. Developers are encouraged to test drive this new UI and provide feedback
The Jakarta Agentic AI 1.0 specification, whose creation was approved in early November 2025, recently delivered a M1 release and a new project website. The August 2026 edition of Azul Payara serves as the first implementation
Spring Framework
The release of Spring Tools 5.4.0 ships with bug fixes, a dependency upgrade to Eclipse IDE 2026-09 and new features such as: the addition of a validation check and a quick fix that replaces the combined use of the @Controller and @ResponseBody annotations with @RestController; adoption of the Spring Modulith @ApplicationModuleListener annotation; and enabling the Claude Code plugin to render a project's logical structure. More details on this release may be found in the release notes.
Open Liberty
The GA release of Open Liberty 26.0.0.9 provides bug fixes, resolutions to numerous CVEs and notable changes such as: elevation of the MCP Server feature (mcp-1.0) from experimental to general availability; and an implementation of the OAuth 2.0 Protected Resource Metadata (RFC 9728) specification that allows developers to enable protected resource metadata when using the OpenID Connect Client (openidConnectClient-1.0) feature.
This release brings breaking changes as the MCP Server feature name has changed from mcpServer-1.0 to mcp-1.0, and the server.xml configuration element has changed from <mcpServer> to <mcp>.
Micronaut
The Micronaut Foundation has released versions 5.1.5 and 5.1.4 (announced here and here, respectively) of the Micronaut Framework, based on Micronaut Core versions 5.1.15 and 5.1.14. Notable changes include: a patch update to Micronaut Data; resolutions to three CVEs; and a dependency upgrade to Netty 4.2.18.Final that addresses numerous CVEs. Further details on these releases may be found in the release notes for version 5.1.5 and version 5.1.4.
Apache Groovy
The first release candidate of Apache Groovy 6.0.0 delivers bug fixes, dependency upgrades and new features such as: a new @GroovyABI annotation that marks methods, which may be called directly from bytecode, as part of the Groovy Application Binary Interface (ABI); an improved JsonSlurper class that adds a maxNumberLength attribute that will not accept a number token greater than that value and throw a JsonException; and an improved XmlNodePrinter class for handling larger documents. More details on this release may be found in the release notes.
RefactorFirst
Jim Bethancourt, principal software consultant at Improving, has released version 0.10.0 of RefactorFirst, a utility that prioritizes the parts of an application that should be refactored. This release provides bug fixes and two new features: JDK 17 as the minimal Java version; and support for Kotlin source file processing such that codebases containing both Java and Kotlin source files are treated as a unified codebase. Further details on this release may be found in the release notes.
ADK for Kotlin
Google has released version 1.0 of the ADK for Kotlin, an agent development kit for building production-ready AI agents in Kotlin and Android. First introduced in May 2026, this new version delivers "full feature parity with ADK 1.0 Core to Kotlin, Java, and Android developers through an idiomatic Kotlin API, and adds Android-first, on-device extensions for building agents on the JVM or on-device." New features include: a new MultiAgentLoader class that provides a fixed set of agents by name to complement the SingleAgentLoader class; and a fluent builder() method, added to the AdkServerConfig class, that allows Java developers to configure a server without the all-arguments data-class constructor. More details on this release may be found in the release notes.
Gradle
The first release candidate of Gradle 9.8.0 delivers new features such as: support for the upcoming release of Java 27 in the Gradle daemon and Java toolchains; support for reusing the Maven mirror repository settings with a simple flag; and a 45% performance improvement in WindowsOS. Further details on this release may be found in the release notes.