DB db = DBMaker.memoryDB().make(); ConcurrentMap map = db.hashMap("map").make(); map.put("something", "here"); 1. MapDB 공식 사이트: mapdb.org/ MapDB MapDB provides Java Maps, Sets, Lists, Queues and other collections backed by off-heap or on-disk storage. It is a hybrid between java collection framework and embedded database engine. It is free and open-source under Apache license. mapdb.org 2. MapDB..