[srazzaque]

I've seen a few reasons in big-corps. To list 2:

1. Old version, and security updates are still required

There's some critical piece of legacy software that has only been tested and observed to work on an old version of the JVM (e.g Oracle JDK 8).

The cost of decommissioning the software OR upgrading and re-testing on a later JDK OR switching to the OpenJDK (without security updates...) is perceived to be more expensive or in breach of company policy versus paying licensing fees.

2. Use of proprietary or deprecated APIs

Either company code or that of a library dependency has reliance on proprietary or undocumented Oracle (or Sun) APIs and toolkits that aren't supported in OpenJDK.

The chances that the existing team members, or the current army of "Spring Boot Microservice Developers" will be able to rationalise or unwind this code in a reasonable time frame is slim.

Though to be fair I haven't seen #2 in some time now.