to implement OData services, which is better Apache Olingo or OData4j?

Question

I have to publish my entities(Database tables) via OData service protocol using Java. I thoroughly checked the options on OData implementation and found two major libraries as Apache Olingo and OData4J.

I could't decide which one is best suitable? I could't find any documents on differences between them.

Answer 1

If you want to use the newest protocol version (v4) you should go with Apache Olingo. There is also SDL OData Framework, but I'm not experienced with this. More info here: http://www.odata.org/libraries/. Apache was taking care of OData since version 2, so I guess that this library is more reliable. On the other hand there are still some open issues in Apache Olingo. Recently the most annoying one from my perspective is: https://issues.apache.org/jira/browse/OLINGO-778

Answer 2

We have built an OData service using Olingo with great success. We have used standard Java Objects with Olingo Annotations to expose them as EdmEntities. Olingo supports JPA as well if you want to expose you DB tables directly.

Prior to deciding on Olingo we explored both options and found it very difficult to find substantial documentation on OData4J.