Java

Railpack builds and deploys Java (including Spring Boot) applications built with Gradle or Maven.

Detection

Your project will be detected as a Java application if any of these conditions are met:

• A build.gradle file exists in the root directory
• A pom.{xml,atom,clj,groovy,rb,scala,yaml,yml} file exists in the root directory

Versions

The Java version is determined in the following order:

• Set via the RAILPACK_JDK_VERSION environment variable
• If the project uses Gradle <= 5, Java 8 is used
• Defaults to 21

Config Variables

Variable	Description	Example
RAILPACK_JDK_VERSION	Override the JDK version	17
RAILPACK_GRADLE_VERSION	Override the Gradle version	8.5