Spring Tool Suite 3.9.1 Supports JDK 9, JUnit 5

Pivotal has released version 3.9.1 of its Spring Tool Suite (STS), the Eclipse-based development environment for building Spring-based enterprise Java applications.

The big news in this point update is out-of-the-box support for the Eclipse Oxygen.1a update release, which supports Java 9 and JUnit 5 Java testing framework. The long-awaited release of Java 9 was announced in October at the annual JavaOne conference. JUnit 5 was announced in June with the annual Eclipse Release Train.

STS provides a ready-to-use environment for implementing, debugging, running and deploying Spring applications. It includes integrations with Pivotal Cloud Foundry, Git, Maven, and AspectJ. This version of the tool suite comes with the developer edition of Pivotal tc Server (release 3.2.8), the drop-in replacement for Apache Tomcat, which is optimized for Spring.

This release also adds support for all the new Java 9 language enhancements; an updated Spring Cloud CLI installation, which is completely user driven (no STS auto-install); refactoring support to convert to application.yml; and a range of new, important bug fixes (organize imports shortcut is back, for example).

There's also an experimental feature: the option to launch Spring Boot apps from within the IDE using the Thin launcher approach, implemented by Dave Syer, the London-based senior consulting engineer who founded Spring Boot, Spring Cloud, Spring Batch and Spring Security OATH. "This approach allows you to create a thin jar without all the dependencies that you have configured in your pom," explains the blog post announcing the release. "Instead, a thin jar launcher is placed and configured into your small JAR file. When the app launches, the thin jar launcher will resolve and fetch the necessary dependencies and launch the boot app."

Although STS 3.9.1 can run on top of a JDK out-of-the-box, the Maven support in Eclipse/STS runs within the JVM of the IDE, and therefore also uses the JDK9 runtime. "While that isn't necessarily a problem," the blog states, "having Maven modules in your build that aren't compatible with Java 9 might cause your project build to fail in Eclipse/STS."

The Spring Framework continues to be one of the most popular programming and configuration models for building modern Java-based enterprise applications on any type of deployment platform. It's an open-source, layered Java/J2EE framework based on code published in SpringSource founder Rod Johnson's book Expert One-on-One Java EE Design and Development (Wrox Press, October 2002).

STS 3.9.2 is scheduled to be released on top of Eclipse Oxygen.2 (4.7.2) in late December 2017.

About the Author

John K. Waters is the editor in chief of a number of sites, with a focus on high-end development, AI and future tech. He's been writing about cutting-edge technologies and culture of Silicon Valley for more than two decades, and he's written more than a dozen books. He also co-scripted the documentary film Silicon Valley: A 100 Year Renaissance, which aired on PBS.  He can be reached at [email protected].