ObjectDB - Object Database for Java/JDO

  ObjectDB for Java/JDO a powerful yet compact Object Database (ODBMS) for Java, written entirely in Java, and compliant with the Java Data Objects (JDO) standard developed by Sun. ObjectDB for Java/JDO is designed to handle efficiently databases of various sizes, from a few KBs to hundreds of GBs. Among its features are small footprint, high performance, rapid development, easy deployment and flexible architecture (1-Tier, 2-Tier or N-Tier).