Service and Service Layer

quick one. What is the difference between a service and a service layer? I could not 开发者_如何学编程find a good answer on internet

In Enterprise Application Architecture, a service layer is (quite literally) a layer of services that define the boundary from external applications (e.g. a website) to your model logic. Multiple services can be part of the service layer. The service layer is a general concept, services are a physical implementation. The difference is kind of like saying "the banking system" vs "a bank".

Straight from the horse's mouth: Martin Fowler's definition of Service Layer

I'm not entirely clear on the context you're looking but I would say that a service layer is a conceptual section of a multilayered system. The service layer generally coordinates functions of lower levels (which may include domain services) and repository data but doesn't include business logic.

A service would be a component implemented within the service layer. For example, a service layer in an ERP application could consist of an HR service, a Finance service, an e-Commerce service etc.

just guessing...

service resides inside service layer. In other words a service layer consists of one or more services

In Enterprise application Service layer :

• The service layer is between the application layer and the business process layer.
• Service layer contains one or more than one service.

• It will be the interface to communicate other application.

  Services comprise unassociated, loosely coupled units of functionality that have no calls to each other embedded in them. Each service implements one action, such as filling out an online application for an account, or viewing an online bank statement, or placing an online booking or airline ticket order. And Service is integral part of Service layer.