org.wso2.balana.combine

Class PolicyCombiningAlgorithm

java.lang.Object

org.wso2.balana.combine.CombiningAlgorithm

org.wso2.balana.combine.PolicyCombiningAlgorithm

Direct Known Subclasses:

DenyOverridesPolicyAlg, DenyOverridesPolicyAlg, DenyUnlessPermitPolicyAlg, FirstApplicablePolicyAlg, OnlyOneApplicablePolicyAlg, PermitOverridesPolicyAlg, PermitOverridesPolicyAlg, PermitUnlessDenyPolicyAlg

public abstract class PolicyCombiningAlgorithm
extends CombiningAlgorithm

The base type for all Policy combining algorithms. Unlike in Rule Combining Algorithms, each policy must be matched before they're evaluated to make sure they apply. Also, in combining policies, obligations must be handled correctly. Specifically, no obligation may be included in the Result that doesn't match the effect being returned. So, if INDETERMINATE or NOT_APPLICABLE is the returned effect, no obligations may be included in the result. If the effect of the combining algorithm is PERMIT or DENY, then obligations with a matching fulfillOn effect are also included in the result.

Since:

1.0

Author:

Seth Proctor, Marco Barreno

Constructor Summary

Constructors

Constructor and Description
PolicyCombiningAlgorithm(URI identifier) Constructor that takes the algorithm's identifier.

Method Summary

Modifier and Type	Method and Description
abstract AbstractResult	combine(EvaluationCtx context, List parameters, List policyElements) Combines the policies based on the context to produce some unified result.

Methods inherited from class org.wso2.balana.combine.CombiningAlgorithm

getIdentifier

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PolicyCombiningAlgorithm

public PolicyCombiningAlgorithm(URI identifier)

Constructor that takes the algorithm's identifier.

Parameters:

identifier - the algorithm's identifier

Method Detail

combine

public abstract AbstractResult combine(EvaluationCtx context,
                                       List parameters,
                                       List policyElements)

Combines the policies based on the context to produce some unified result. This is the one function of a combining algorithm.

Note that unlike in the RuleCombiningAlgorithms, here you must explicitly match the sub-policies to make sure that you should consider them, and you must handle Obligations.

Specified by:

combine in class CombiningAlgorithm

Parameters:

context - the representation of the request

parameters - a (possibly empty) non-null List of CombinerParameters

policyElements - a List of CombinerElements

Returns:

a single unified result based on the combining logic