Is there a open-source off-heap cache solution for Java?

Question

Is there any open-source alternative for Terracotta BigMemory?

Actually I didn't even manage to find any commercial alternative. I'm interested in pure Java solution which will work inside JVM without any JNI and C-backed solution.

Answer 1

There is a very good cache solution named MapDB(JDBM4 formerly). It supports HashMap and TreeMap But it is only application embedded. It also support persistent file based cache.

Example for off heap cache:

DB db = DBMaker.newDirectMemoryDB().make(); ConcurrentNavigableMap<Integer, String> map = db.getTreeMap("MyCache"); 

Or persistent file based cache:

DB db = DBMaker.newFileDB(new File("/home/collection.db")).closeOnJvmShutdown().make(); ConcurrentNavigableMap<Integer,String> map = db.getTreeMap("MyCache");