Heroku's commitment to developer productivity shines through in its powerful buildpack system. They handle the heavy lifting of building your app, letting you focus on what matters most: writing code. A prime example is the Heroku Java buildpack, a versatile tool that simplifies deploying Java applications, especially those built with popular frameworks like Spring Boot, Quarkus, and Micronaut.
One of the core strengths of Heroku buildpacks is their automatic nature. They intelligently detect your application's language and framework, fetching the necessary build tools and configuring the Heroku platform to run your app seamlessly. This means no more wrestling with server configurations or deployment scripts – Heroku handles it all.
Beyond just building your application, our Java Buildpacks go a step further by understanding the nuances of different Java frameworks and tools. They automatically inject framework-specific configurations, such as database connection details for Postgres, eliminating the need for manual setup. This deep integration significantly reduces the friction of deploying complex Java applications. You don't have to teach Heroku how to run your Spring Boot, Quarkus, or Micronaut app, and in some cases you don't have to teach these frameworks how to interact with Heroku services either. In many cases, even a Procfile becomes optional! Let's take a closer look at how the Java Buildpack supports these popular development frameworks.
Spring Boot Development Framework
The Maven or Gradle buildpack recognizes your Spring Boot project by inspecting your build definition, for example your pom.xml file. It automatically packages your app into an executable JAR, and configures the environment to run it using the embedded web server. It also helps out with Spring specific environment variables, ensuring your Spring Boot app behaves as expected when working with databases. Database connections are automatically configured using SPRING_ (such as SPRING_DATASOURCE_URL), so Spring automatically detects your use of the Heroku Postgres add-on. This is also true for our Heroku Key Value Store add-on, whereby the SPRING_REDIS_URL environment variable is automatically set. In many cases, a Procfile isn’t necessary since the buildpack can determine the main JAR file automatically and adds a default process for your application such as: web: java -Dserver.port=\$PORT \$JAVA_OPTS -jar $jarFile.
Quarkus Development Framework
We recently added support for Quarkus, known for its focus on developer joy. The Java (Maven) or Java (Gradle) buildpacks recognize your Quarkus project by inspecting your build definition. You can omit the usual Procfile and Heroku will default to Quarkus’ runner JAR automatically: java -Dquarkus.http.port=\$PORT \$JAVA_OPTS -jar build/quarkus-app/quarkus-run.jar.
Micronaut Development Framework
Micronaut, another framework designed for speed and efficiency, also benefits from the Java Buildpack's intelligent automation. Just like with Spring Boot and Quarkus, database connections via DATABASE_URL and JDBC_DATABASE_URL and other environment-specific settings are handled automatically. You can omit the usual Procfile and Heroku will default to this automatically: java -Dmicronaut.server.port=\$PORT \$JAVA_OPTS -jar build/libs/*.jar.
Enhance Java Virtual Machine (JVM) Apps with Runtime Metrics
Heroku's Language Runtime Metrics provide JVM metrics for your application, displayed in the Heroku Dashboard. This feature complements our existing system-level metrics by offering insights specific to your application's execution, such as memory usage and garbage collection. These more granular metrics offer a clearer picture of your code's behavior.
Heroku automatically configures your application to collect these metrics via a light-weight JVM agent. No configuration necessary.
Beyond Java: Heroku's JVM Language Support
Apart from offering excellent support for building Java applications, Heroku offers support for additional JVM languages in Scala and Clojure. The buildpacks for those languages offer a similar suite of features backed by the sbt and Leiningen build tools.
Building great apps with Heroku and Java
Looking through our Heroku customer stories we can see that our customers are enjoying our Java support, building engagement apps, helping with cloud adoption and driving growth by leveraging Heroku’s ability to elastically scale compute intensive workloads.
eCommerce Site & business platform: Improve user or employee engagement, and retention.
Customer Story: Goodshuffle ProCloud Adoption: Replatforming legacy back-end services.
Customer Story: DovetailEngines & APIs: Project customer growth.
Customer Story: PensionBee
Extend Salesforce with Java: Heroku AppLink & Eventing
Yes, and in fact, with any language supported by Heroku, it's possible to extend your Flow, Apex, and Agentforce experiences with code, frameworks, and tools you're familiar with from the Java ecosystem. Even if you haven't used Java before, you'll find its syntax similar to that of Apex. Check out our latest Heroku Eventing and AppLink pilot samples written in Java to find out more!
Heroku Java Buildpacks: Simplifying Deployment and Configuration
Heroku's Java buildpacks are powerful tools that significantly simplify deploying JVM applications. By automating the build process, injecting framework-specific configurations, and handling runtime setup, it lets developers focus on writing code, not managing framework configuration. Here are some useful articles the Heroku DevCenter site:
- Getting started with Java and Maven
- Getting started with Java and Gradle
- Working with Spring Boot
- Connecting to Relational Databases on Heroku with Java
To submit feedback on your favorite JVM language, framework, or packaging tool, please connect with us via the Heroku GitHub roadmap. We welcome your ideas and suggestions.