I\'m using Derby ij to look into my local Apache Derby database. It\'s just a folder and I connect to it like this:
connect \'jdbc:derby:C:\\Users\\Torben\\
I use DBeaver Community Edition (free and open source).
When comparing DBeaver CE 6.0.2 (2019-04-08) against SQuirreL 3.9.1 (2019-02-24) I noticed that SQuirreL does not show some database objects (eg. sequences).
DBeaver supports intellisense / auto-completion, updating table rows in-place (ie. "select for update"), and can globally apply filters on schemas and catalogs in connection settings (eg. exclude SYS schemas from the object tree display). It can also run pre- and post-connection scripts (handy for initialising an ij session with preferences eg. protocols).