在Java中使用存储库模式时，可以将单个Manager / Controller用于3个不同的存储库吗？

Question

I have 3 repositories that need to communicate with each other. Can I handle the logic of all 3 repositories in a single Manager or is it a better practice to create different Managers for each Repository and make them communicate with each other using another Manager (that will directly communicate with the UI)?

Context:

It's basically an app for managing restaurant orders.

The 3 Repositories are:

• ProductRepository - the available products
• TableRepository - all the tables in the restaurant
• OrderRepository - one order consists of a tuple (product_id, table_id)

The manager must validate the data, create Product, Table and Order objects and save them to the correct Repository.

Answer 1

If classes / resources depend up on one other, there is (these days) mostly a Dependency Injection framework, handling the creation of these resources, and also Injecting them, in those who need them.

The best known DI libraries for Java are

• Google Guice
• Spring DI