This is a pure-Java implementation of Berkeley DB by SleepyCat (now Oracle). Java-1.5 is required for building, although the result should be usable with 1.4 too. From the WWW: http://www.oracle.com/database/berkeley-db/index.html "Berkeley DB JE was designed from the ground up in Java. It takes full advantage of the Java environment. The Berkeley DB JE API provides a Java Collections-style interface, as well as a programmatic interface similar to the Berkeley DB API. Berkeley DB JE is different from all other Java databases available today. Berkeley DB JE is not a relational engine built in Java. It is a Berkeley DB-style embedded store, with an interface designed for programmers, not DBAs. Berkeley DB JE's architecture employs a log-based, no-overwrite storage system, enabling high concurrency and speed while providing ACID transactions and record-level locking. Berkeley DB JE efficiently caches most commonly used data in memory, without exceeding application-specified limits. In this way Berkeley DB JE works with an application to use available JVM resources while providing access to very large data sets. The Berkeley DB JE architecture provides an underlying storage layer for any Java application requiring high performance, transactional integrity and recoverability."