SmartCLient already brings several interesting values when dealing with SQL databases.
I suggest the exact same features regarding the support of a Java NoSQL Database with a friendly Apache 2.0 licence for SmartClient : OrientDB (http://www.orientechnologies.com/). It's at the same time a very fast document db, object db (as a wrapper built on top of the document database) and graph database supporting ACID transactions and bringing soon clustering capabilities.
I suggest the exact same features regarding the support of a Java NoSQL Database with a friendly Apache 2.0 licence for SmartClient : OrientDB (http://www.orientechnologies.com/). It's at the same time a very fast document db, object db (as a wrapper built on top of the document database) and graph database supporting ACID transactions and bringing soon clustering capabilities.