CHA provides CHA Facade as its Interface. CHA Factory mode creates the interface implementation. As a result, CHA scalability is enhance.
You can have Local mode CHA, Remote mode CHA (including Persistence shared CHA and Memory shared CHA), and your own CHA implementation as shown in the following figure:
The following table shows the relations among different types of Contexts and different modes of CHA.
CHA | Local Context Supported | Remote Context Supported | EJB Needed | Persistence Needed |
---|---|---|---|---|
Local Mode CHA | Yes (created from local) | No | No | No |
Memory Shared CHA | Yes (created from CHA EJB) | Yes | Yes | No |
Persistence Shared CHA | Yes (created from CHA EJB) | Yes | Yes | Yes |