Java DB is an open source Apache Derby database
supported by Sun. Java DB is completely written in the Java programming language
having the functionality write once run everywhere. It is easy to use, having
fully featured set, small footprint and standards compliance that make it ideal
database for Java developers. It can be embedded into any Java applications
without any administration required by the developer. It is also useful for
client server mode.
The Java Database Connectivity (JDBC) API is provides database-independent connectivity between the Java programming language with the wide range of databases such as SQL and other tabular data sources, such as spreadsheets or flat files. JDBC also provides the concept of write once run anywhere.