Make multiplatform project to build and run in JDK 8 and 11

Question

I want to migrate my Maven project to JDK 11. But I want to keep support for JDK 8.

Problems so far are:

• <maven.compiler.release> is supported since Java 9. How to use it in JDK 11 but ignore it in JDK 8?
• I'm using Apache HttpClient in Java 8. Java 11 has a new built in HTTP client and Apache HttpClient 4.x has some issues on Java 11. Is there a way to use JDK's HttpClient in Java 11 and Apache's in Java 8?

How to deal with those problems? Is it possible to make a project work in different JDKs like this? Or is the only way to keep the smallest commonality for everything?

Answer 1

If you still have to support Java 8, stay on Java 8. Chances are that you will find more problems when trying to achieve this and it might cost you a lot of time.

When you can get rid of Java 8 support, migrate the whole application once to Java 11 and save your time right now.