How to upgrade Java Version in AWS EBS

When upgrading the Java version in AWS Elastic Beanstalk, you cannot directly change the major runtime version (like Java 7 to Java 8) through a simple platform update. This is why the option appears disabled in your interface.

For major Java version upgrades in Elastic Beanstalk, you need to perform a Blue/Green deployment (referred to as Method 2 in AWS documentation). This involves:

1. Creating a new environment with the desired Java version
2. Deploying your application to this new environment
3. Testing to ensure compatibility and fixing any issues
4. Swapping the environment URLs once you're satisfied with the new environment
5. Terminating the old environment after confirming the new one works properly

This approach is necessary because changing major runtime versions often requires application code changes and thorough testing.

Alternatively, if you're working with a Java application that needs modernization, you could consider using Amazon Q Developer's Java upgrade capabilities. This tool can help transform your code for Java language upgrades (such as Java 8 to 17/21, Java 11 to 17/21, or Java 17 to 21). Amazon Q makes minimal necessary changes to make your code compatible with the target Java version and can also help upgrade third-party dependencies.

The key point is that major version upgrades in Elastic Beanstalk require creating a new environment rather than updating an existing one, which explains why the option is disabled in your interface.
Sources
Updating your Elastic Beanstalk environment's platform version - AWS Elastic Beanstalk
How Amazon Q Developer transforms code for Java language upgrades - Amazon Q Developer
How do I upgrade my EBS environment from Node 18 to 20? | AWS re:Post