jydbconsole is a database console inspired by psql - terminal-based front-end to PostgreSQL. Is written in jython and uses JDBC drivers to talk to databases, uses terminal console (unix only) or java swing as an user interface.
dbmjui is graphical user interface written in Java one can use to manage multiple SAPDB instances.
It tends to mimic dbmgui but as it is written in Java, it is usable on every platform where a JVM is available.