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Dependencies between components in these sets must ONLY go up the list. For example components in plugins can depend on components in applications, but components in applications can not depend on components in specialpurposeplugins.
Components Within Sets
framework
The framework is the underlying data structures and utilities that supply the essential common features used by the base applications and the extended components. These higher level components will have many dependencies on the framework components. There should be no dependencies in the framework on other parts of OFBiz but a few have crept in. They are show shown as the gray arrows in the diagram.
There should be a full discussion in on the mailing list before any new dependencies are added. Actually, they should be avoided and even an effort to remove the existing one would be welcome. Framework-only distribution is a the first step in this direction...
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The base applications components depend on each other as shown in the diagram. The reason these dependencies are needed is because the components are organized according to high-level business concepts and in the real world business processes tend to jump between many of them. In technical terms, this results in foreign keys from an entity in one component to an entity in another, and to service calls from services in one component to services in another, and other similar effects.
While components can depend on one another in the base applications set they should follow the established priority of dependencies. In the diagram below you see existing dependencies and the component dependency priority going from the top of the page down (in other words components higher on the page depend depends on components lower on the page).
Whenever some data structure or feature could go in multiple components , or could depend on elements in multiple components, the design should ensure that lower level components don't depend on something in the higher level ones.
The gray arrows in the diagram represent dependencies that violate the rule and are subject of on-going ongoing discussions about how to fix them.
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An overview of the plugins applications can be found here:
User-define defined components that are not part of OFBiz, as plugins to OFBiz. The same guidelines are recommended here as well.
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