Is OLAP4J (Java library for connecting to XMLA services) dead? The things that suggest it is are:
If it is dead, then is there a suitable replacement?
I am the original author of olap4j, and also own the www.olap4j.org domain. Development has certainly been slow recently, but I wouldn't say the project is dead. If people have pull requests to contribute, then I will be happy to commit them to the project and make new releases.
I don't know of any alternatives to olap4j. The idea that you can connect to any XML/A-compliant OLAP engine via Java, get metadata in the same way that you would from a JDBC data source, and that your code depends only on the API, not a particular driver implementation, is still a good one.