| Interface Summary | 
| Condition | The class Conditiondefines an interface 
 to allow pluggable condition. | 
| PolicyListener | The interface PolicyListenerdefines an interface 
 for listeners that would register with policy framework 
 to receive notifications whenever a policy is added, removed 
 or changed | 
| Referral | interface to facilitate delegating policy evaluation 
  There would be many implementations with different policy delegation 
  mechanisms such as delegating to peer organizations only 
  or delegating to sub organizations only. | 
| ResourceName | The interface ResourceManipulatorprovides
 methods to determine the hierarchy of resource names. | 
| ResponseProvider |  | 
| Subject | The class Subjectdefines a collection
 of users (or subject) to whom the specified policy is applied. | 
 
Provides interfaces for writing custom Policy plugins for Conditons, Subjects, Referrals and Resources.