megadotnet / velocity-native

Velocity-native Runtime Hints

Intro

       Spring Boot 3 native applications require compile time definitions of which reflection data needs to be available at runtime. 
   We could provide this info for its own classes by adding a RuntimeHintsRegistrar.

Spring Boot 3: Unleashing Native Power with GraalVM

Spring Boot 3 brings exciting advancements, and one of the most notable is its seamless integration with GraalVM native image support. This powerful combination enables you to create self-contained executables of your Spring Boot applications, offering significant benefits like:

• Faster startup times: Native images eliminate the need for a full JVM, resulting in dramatically faster application launches.
• Reduced memory footprint: Native executables only contain the code your application needs, leading to lower memory consumption and improved resource efficiency.
• Improved portability: Native images can run on various platforms without requiring a specific Java environment, simplifying deployment and distribution.

This article guides you through leveraging Spring Boot 3's native capabilities with GraalVM:

Prerequisites:

• Java 17 or later: Spring Boot 3 requires Java 17 for native image generation.
• GraalVM: Download and install GraalVM from https://www.graalvm.org/.
• Spring Boot 3 application: Ensure you have a Spring Boot 3 project set up.

Steps:

1. Add GraalVM plugin:

   In your project's build configuration (e.g., pom.xml for Maven or build.gradle for Gradle), add the GraalVM native plugin:

   <plugin>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-native</artifactId>
       <version>3.0.x</version>
   </plugin>

2. Build the native image:

   Use the following command to build a native image of your application:

   ./gradlew nativeImage  # For Gradle
   mvn spring-boot:build-image  # For Maven

   This generates a native executable named after your application's main class (e.g., my-app).

3. Run the native image:

   Execute the generated native image directly:

   ./my-app

Additional considerations:

• Resource handling: Native images require explicit inclusion of required resources during build time. Refer to the Spring Boot documentation for details on managing resources in native images.
• Reflection and dynamic code: Native images might have limitations with reflection and dynamic code loading. Ensure your application uses these features sparingly or consider alternative approaches.

Exploring further:

• Spring Boot documentation on GraalVM native image support: https://docs.spring.io/spring-boot/docs/current/reference/html/native-image.html
• GraalVM documentation: https://www.graalvm.org/

By embracing Spring Boot 3's native capabilities, you can significantly enhance your application's performance, portability, and resource efficiency. With GraalVM's support, you can create self-contained executables that streamline deployment and operation, empowering your applications to thrive in diverse environments.