In memory and embeddable OLAP implementation compatible with olap4j

I am looking for an OLAP implementation, which could be embedded in a java application. The best -- but not necessarily -- if I could use olap4j to connect to it. I need such a library for testing purposes of my application to evaluate ideas before go for a standalone OLAP se开发者_StackOverflowrver.

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Mondrian seems to be the perfect solution. It is implemented in pure Java, it is embeddable, and its native interface is olap4j. If you need a database to be embedded also, use an embedded Java database such as apache derby or hsqldb.

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The Mondrian project is the reference implementation of the olap4j project. I work on both projects and know all the ins and outs of both. They will play nicely together.

By using olap4j, you also gain access to olap4j's XML/A driver to connect to SSAS, SAP and Palo. It might even work on Oracle's Essbase. We haven't tried it yet.

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You may have a look to icCube. It can used as a standalone OLAP server but as well as a component that you can embed into your JAVA application. For more details about the last point, you can ask in our forum. Cheers.

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Not sure whether you are looking for open source or commercial product.

Active Pivot from QuartetFS is in memory OLAP cube written in Java and provide API to customize. It support OLAP4J, XMLA interaction and yes it is used in production by many financial companies.