Arch4J is an open source Java architecture framework that provides an infrastructure of services to support enterprise development. The framework specifies what the services are, but does not does not dictate how they are implemented. The framework gives business logic developers a standard, stable interface to all of the non-business code. Included are a layered set of modular service providers that facilitate development of business services, data access, messaging, domain validation, logging, property file management, an exception framework, a code generator and more.