Scalable Human Blog

Java, the long-standing, versatile player in the world of programming languages, periodically releases new versions that bring about fresh features, enhanced performance, and better security. As a result, it’s crucial to keep your Spring Boot application updated with the latest Java version. However, moving to a newer Java version isn’t as simple as flipping a switch. It requires careful consideration and meticulous planning to avoid compatibility issues and other unforeseen complications. Let’s delve into the key aspects you should keep in mind while upgrading the Java version for your Spring Boot application.

Assess the Application’s Compatibility

Firstly, thoroughly examine your application’s compatibility with the new Java version. This involves reviewing the current libraries, frameworks, and dependencies to ensure they support the target Java version. Always refer to the official documentation for this information. Spring Boot, in particular, is regularly updated to support new Java releases, so verify that your Spring Boot version aligns with the Java version you’re targeting.

<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.5.4</version> <!--ensure this supports your target Java version--> </parent>

Verify Your Build Tools and CI/CD Pipelines

Confirm that your build tools (like Maven or Gradle) and CI/CD pipelines also support the new Java version. Often, these tools need updates to run with newer Java versions.

<build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.8.0</version> <configuration> <source>11</source> <!--target Java version--> <target>11</target> <!--target Java version--> </configuration> </plugin> </plugins> </build>

Test with -Werror and -Xlint:deprecation

Use the -Werror flag, which treats warnings as errors, and -Xlint:deprecation, which provides details about the use of deprecated APIs. These flags can help you identify any deprecated or removed APIs that your application uses.

Utilize JDeprScan Tool

Java 9 introduced a tool called jdeprscan, which scans an application’s bytecode for uses of deprecated APIs. Running this tool before upgrading can help identify potential issues.

Perform Comprehensive Testing

Once you’ve updated to the new Java version and addressed any warnings or deprecations, it’s time to thoroughly test your application. This includes unit tests, integration tests, and end-to-end tests to ensure your application works as expected with the new Java version.

Leverage Docker for Testing

If possible, use Docker for testing the new Java version. With Docker, you can create a separate container with the new Java version, leaving your existing setup undisturbed.

FROM openjdk:11-jdk COPY ./target/my-application.jar /usr/app/ WORKDIR /usr/app RUN sh -c 'touch my-application.jar' ENTRYPOINT ["java","-jar","my-application.jar"]

Plan a Gradual Rollout

Consider rolling out the updated application gradually to monitor its performance and catch any unforeseen issues. Techniques like Canary deployments or Blue/Green deployments can be helpful here.

Summary

Upgrading the Java version for your Spring Boot application is a significant task that can introduce new opportunities as well as potential risks. Prioritise thorough preparation, use the right tools, and adhere to best practices to ensure a smooth transition. While the upgrade process may seem daunting, the benefits of using the latest Java version – such as improved performance, enhanced security, and access to new features – make the effort worthwhile.

📚 Further Reading & Related Topics

If you’re exploring Java version upgrades for Spring Boot applications, these related articles will provide deeper insights:

• Spring Boot vs. Quarkus: A TL;DR Comparison – Compare how different Java frameworks handle performance and compatibility when upgrading versions.

• Embracing Modern Java: Strategies for Upgrading and Optimizing Enterprise Applications – Learn best practices for modernizing and optimizing Spring Boot applications while upgrading Java versions.