Java DB Client-server technology - centralized DB - How?

Question

I have a project this year. It is about developing a Java application with a database for circulating and validating documents between the manager, secretary and head of finance.

My question is: How to make the database accesible by all, since the application will be installed on computers that I mentioned above, do I have to install it (the database) on these computers and this modification, the constraints of consistency and integrity of the database will be violated.

That's my problem yet.

Note that before I developed an application for managing a library and it was a client post.

Is there a possibility (or technology in Java) to put the database on the web and there will be accessible by all, or make it accessible from a computer that I realize as a server (client-server).

I can do research if you can give me a solution or a sign

I would be grateful for your help or giving links for Tutorials. Awaiting your response.

Best regards,