Sun OpenSSO Enterprise 8.0 Developer's Guide


com.sun.identity.policy.PolicyEvaluator evaluates policy privileges and provides policy decisions. It provides methods to evaluate access to one resource or a hierarchy of resources, and supports both boolean and non-boolean type policies. A valid session token of the principal attempting access is required to invoke any method of this class. A PolicyEvaluator class is created by calling the constructor with a service name. Key public methods of this class include:


Evaluates a policy associated with the given resource and returns a boolean-type value indicating an allow or deny decision.


Evaluates policies and returns a decision as to whether the associated principal can perform the specified actions on the specified resource.


A ResourceResult contains policy decisions regarding a particular protected resource and its sub resources. getResourceResults() obtains these policy decisions. Possible values for the scope of objects retrieved are ResourceResult.SELF_SCOPE (returns an object that contains the policy decision for the specified resource only), ResourceResult.SUBTREE_SCOPE (includes policy decisions for the specified resource and its sub-resources), and ResourceResult.STRICT_SUBTREE_SCOPE (returns an object that contains one policy decision regarding the resourceName only). For example, the PolicyEvaluator class can be used to display links for a list of resources to which an authenticated user has access. The getResourceResults() method can be used to retrieve a list of resources to which the user has access from a defined resourceName parameter — a URL in the form http://host.domain:port. The resources are returned as a PolicyDecision object based on the user’s policies. If the user is allowed to access resources on different servers, this method needs to be called for each server.

Not all resources that have policy decisions are accessible to the user. Access depends on the ActionDecision() value contained in policy decisions.