This is an unofficial porting of the Java implementation of Hessian to Jakarta EE 10; Jakarta EE 10 requires Java 11+.
It is based on the source code of Hessian version 4.0.66 (actually the latest one), however note that versions 4.0.63 through 4.0.66 have no change in the source code.
Before creating it, I quickly evaluated some alternatives but Hessian still seems the best in terms of ease of use.
Official Hessian releases are not built by Maven and the official source code does not follow the standard Maven directory layout, however it does provide a POM in the maven2 folder. I adapted that POM without changing the directory layout to keep the number of changes as small as possible. You can run mvn build commands in the maven2 folder.
The artifacts of this project are not available on Maven Central (I deploy them to my company's repo).
If you are using an old version of Spring and you are planning to upgrade it, note that HessianServiceExporter was deprecated and then removed so now you have to use HessianServlet directly. A working example is available at hessian-demo. You can use it also to test this library.