SunTM's XACML Implementation for JavaTM

Class PolicyCombiningAlgorithm

  extended bycom.sun.xacml.combine.CombiningAlgorithm
      extended bycom.sun.xacml.combine.PolicyCombiningAlgorithm
Direct Known Subclasses:
DenyOverridesPolicyAlg, FirstApplicablePolicyAlg, OnlyOneApplicablePolicyAlg, PermitOverridesPolicyAlg

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.


Constructor Summary
PolicyCombiningAlgorithm(URI identifier)
          Constructor that takes the algorithm's identifier.
Method Summary
abstract  Result combine(EvaluationCtx context, List policies)
          Combines the policies based on the context to produce some unified result.
Methods inherited from class com.sun.xacml.combine.CombiningAlgorithm
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail


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

identifier - the algorithm's identifier
Method Detail


public abstract Result combine(EvaluationCtx context,
                               List policies)
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
context - the representation of the request
policies - the policies to combine
a single unified result based on the combining logic

Sun's XACML Implementation Version 1.2

Copyright 2003-2004 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.

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