JDBC driver for derby 10.15.2.0?

Question

I now understand this, which effectively solves my question:

• Derby doesn't require you to load any driver explicitly, it uses the services mechanism to handle this (services pre-date JPMS, so yes, it works without modules). Of course, out of date documenation that still describes loading a driver doesn't really help.
• My actual problem was my failure to understand a couple of things, first, the format of the derby jdbc url, second that the ij tool can create an embedded database.
• In particular the url I used in ij (jdbc:derby:firstdb noted below) is an embedded url. This meant that trying to connect to it using a network url from the client code was bogus. The client created a new db of its own, but didn't interact with the ij one.

Anyway, hopefully some of this might help others, so I'll just leave this here. Fingers crossed someone can find time to update the derby docs, and in particular the getting started guide, to make these critical concepts a bit clearer from the outset.

----- original question -----

I need to do some simple experiments using JDBC in Java, and thought that running up a derby database should be a simple route to that.

I have installed derby, and used the "ij" tool to create a table and get some data into it. I can read that data back using ij too.

However, when I try to connect to this using actual Java code, things go badly. This is one of those situations where I've tried several things, and each fails differently, so I hope you'll all forgive this getting a bit fuzzy edged. But these are the key points of what I've tried/failed so far.

• This is a maven project, and there is a dependency in place for artifactId "derbyclient" version 10.15.2.0
• The ij tool connects to my database (which is on the localhost, but not "embedded") successfully using the url jdbc:derby:firstdb
• The docs that I found (finally!) that talked somewhat about non-embedded mode said the driver should be org.apache.derby.jdbc.ClientDriver, but that class is not found. I found notes in the gihub for the liquibase project that said this is now org.apache.derby.client.ClientAutoloadedDriver. Using that classname, doesn't throw the class not found error, which seems like a step forward.
• Although the above driver loads, the jdbc url shown above fails with "No suitable driver for jdbc:derby:firstdb"
• I found other notes that suggested the url should be of the form jdbc:derby://localhost/firstdb however, that says "The connection was refused because the database firstdb was not found". I've tried a couple of variations of naming the db, but they resulted in "no suitable driver" again.
• At the prompting of g00se in the comments, I went looking for the ClientDriver that I noted above was not found. I discovered this in the main derby distribution in a file derbytools.jar, but not in any of the jars that maven loaded. I tried executing this using a hand-built command line so I could put the derbytools on the classpath. This allowed that to be loaded as a driver, but it connects to an in-JVM database (which works, I can do stuff with this). However, it does not connect to the running network server which is what I want to achieve. When I try to force its hand by using a URL of the form jdbc:derby://localhost:1527/firstdb, it again fails telling me the database was not found.
• I've also discovered that there seems to be no need to do the "Class.forName" thing anyway, nor to be concerned about having ClientDriver on the classpath. Somehow a driver is loaded and available when I do DriverManager.getConnection. However, with the URLs I've tried, I have utterly failed to make it connect to the network server, it always connects to an in-JVM server (which works, but isn't where I want to connect.)

Can anyone tell me how to get this to work?