The idea behind this project is to build something similar to DDDSample. But using slightly different approach. I'll try to use ideas and principles behind:

• Hexagonal architecture
• Clean architecture
• Use case driven development

Here is an article on Medium which will comment on the interesting points and decisions behind this implementation.

This application is based heavily on the original DDDSample application by Citerus AB and Domain Language.

The original work is distributed under the MIT licence. I've included the original licence with this project.

Wherever possible, I'll try to mention the original code which was consulted for any specific implementation point.

This application is a standard Spring Boot application. There is also a Docker compose file with a Postgres database, which should be started prior to the execution of the application. You may need to start the database for some integration tests as well.

To be able to explore the relational model used by DDDSample, we can add an embedded web server to the original application. There is an example configuration available here: HsqlDbServerConfig.java.

To launch the server, you need hsqldb-2.4.0.jar (available from Maven central):

on Unix

java -cp ~/.m2/repository/org/hsqldb/hsqldb/2.4.0/hsqldb-2.4.0.jar org.hsqldb.util.DatabaseManagerSwing

or on Windows

java -cp %HOME%/.m2/repository/org/hsqldb/hsqldb/2.4.0/hsqldb-2.4.0.jar org.hsqldb.util.DatabaseManagerSwing

This should start the UI of the DB viewer. The type of connection to use is "HSQL Database Engine WebServer" and JDBC URL to use is jdbc:hsqldb:hsql://localhost/dddsample.