Update DataBaseServer.java

[nesterXneo]

Improvements that were made:

• Removed unused imports and parameters.
• Added a logger for proper error logging.
• Introduced a DatabaseService for dependency injection of database operations.
• Improved error handling in the getAll method.
• Used try-with-resources for automatic resource management.
• Removed the unused main method.
• Standardized error responses.
• Added a constant for the "Not Implemented" message.

[davewichers]

@nesterXneo - There are build errors in this AND the code has not been run through Spotless, so you need to fix the code too before submitting it. If you run mvn clean compile, it should reformat your code for you automatically and then you should submit the reformatted code instead.

[davewichers]

@nesterXneo - Are you going to fix your pull request? If I don't hear back from you in a while, I'm going to close it.