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#include <ball_attributecontext.h>
Public Member Functions | |
AttributeContext_RuleEvaluationCache () | |
void | clear () |
RuleSet::MaskType | update (bsls::Types::Int64 sequenceNumber, RuleSet::MaskType relevantRulesMask, const RuleSet &rules, const AttributeContainerList &attributes) |
bool | isDataAvailable (bsls::Types::Int64 sequenceNumber, RuleSet::MaskType relevantRulesMask) const |
RuleSet::MaskType | knownActiveRules () const |
bsl::ostream & | print (bsl::ostream &stream, int level=0, int spacesPerLevel=4) const |
This is an implementation type of AttributeContext
and should not be used by clients of this package. A rule evaluation cache is a mechanism for evaluating and caching whether a rule is active. A rule is considered active if all of its attributes are satisfied by the collection of attributes held in a AttributeContainerList
object (i.e., Rule::evaluate
returns true
for the AttributeContainerList
object). The rules this cache evaluates are contained in a RuleSet
object. RuleSet::MaskType
is a bit mask for a rule set, where each bit is a boolean value associated with the rule at the corresponding index in a rule set. An AttributeContext
determines, using the isDataAvailable
method, if a particular set of rules (described using a bit mask) have already been evaluated. A context accesses the current cache of rule evaluations using the knownActiveRules
method. Finally, a context updates the cache of rule evaluations using the update
method. Note that the isDataAvailable
method should be used prior to using knownActiveRules
in order to ensure the relevant rules have been evaluated and that those evaluations are up-to-date.
See Component ball_attributecontext
ball::AttributeContext_RuleEvaluationCache::AttributeContext_RuleEvaluationCache | ( | ) |
Create an empty rule evaluation cache having a sequence number of -1.
void ball::AttributeContext_RuleEvaluationCache::clear | ( | ) |
Clear any currently cached rule evaluation data, restoring this object to its default constructed state (empty).
RuleSet::MaskType ball::AttributeContext_RuleEvaluationCache::update | ( | bsls::Types::Int64 | sequenceNumber, | |
RuleSet::MaskType | relevantRulesMask, | |||
const RuleSet & | rules, | |||
const AttributeContainerList & | attributes | |||
) |
Update, for the specified sequenceNumber
, the cache for those rules indicated by the specified relevantRulesMask
bit mask in the specified set of rules
, by evaluating those rules for the specified attributes
; return the bit mask indicating those rules that are known to be active. If a bit in the returned bit mask value is set to 1, the rule at the corresponding index in rules
is "active"; however, if a bit is set to 0, the corresponding rule is either not active or has not been evaluated. This operation does, however, guarantee that all the rules indicated by the relevantRulesMask
will be evaluated. A particular rule is considered "active" if all of its attributes are satisfied by attributes
(i.e., if Rule::evaluate
returns true
for attributes
). The behavior is undefined unless rules
is not modified during this operation (i.e., any lock associated with rules
must be locked during this operation).
bool ball::AttributeContext_RuleEvaluationCache::isDataAvailable | ( | bsls::Types::Int64 | sequenceNumber, | |
RuleSet::MaskType | relevantRulesMask | |||
) | const |
Return true
if this cache contains up-to-date cached rule evaluations having the specified sequenceNumber
for the set of rules indicated by the specified relevantRulesMask
bit mask, and false
otherwise.
RuleSet::MaskType ball::AttributeContext_RuleEvaluationCache::knownActiveRules | ( | ) | const |
Return a bit mask indicating those rules, from the set of rules provided in the last call to update
, that are known to be active (as of that last call to update
). If a bit in the returned value is set to 1, the rule at the corresponding index is active; however, if a bit is set to 0, the corresponding rule is either not active or has not been evaluated. Note that isDataAvailable
should be called to test if this cache contains up-to-date evaluated rule information for the rules in which they are interested before using the result of this method.
bsl::ostream& ball::AttributeContext_RuleEvaluationCache::print | ( | bsl::ostream & | stream, | |
int | level = 0 , |
|||
int | spacesPerLevel = 4 | |||
) | const |
Format this object to the specified output stream
at the (absolute value of) the optionally specified indentation level
and return a reference to stream
. If level
is specified, optionally specify spacesPerLevel
, the number of spaces per indentation level for this and all of its nested objects. If level
is negative, suppress indentation of the first line. If spacesPerLevel
is negative, format the entire output on one line, suppressing all but the initial indentation (as governed by level
). If stream
is not valid on entry, this operation has no effect.