com.bea.p13n.rules.advislets
Class RulesAdvisletImpl

java.lang.Object
  com.bea.p13n.advisor.AbstractAdvislet
      com.bea.p13n.rules.advislets.RulesAdvisletImpl

All Implemented Interfaces:

AdviceConstants, AdviceRequestConstants, Advislet, AdvisletChainElement

public class RulesAdvisletImpl

extends AbstractAdvislet

This class is the implementation class for a generic Advislet that handles rules based advice. It is designed to be extended by Advislets that wish to make use of the rules engine and provides a number of methods that can be overridden to change some of the default behaviour.

Required inputs to the Advislet are:

• RULES_FILTER_CLASS_NAME - the name of an ObjectFilter class that should be used to filter the objects returned by the RulesManager.
• RULES_INPUT_OBJECTS - a Collection of input objects to be passed to the RulesManager.

The output objects from rule evaluation are placed in a List in the Advice with the RESULTS key.

Field Summary

static String	IGNORE_RULE_NAME The key name for the optional ignore rule name parameter.
static String	IGNORE_RULESET_NOT_FOUND The key name for the optional ignore rule name parameter.
static String	RULESET_NAME The key name for the optional rule set name parameter.

Fields inherited from class com.bea.p13n.advisor.AbstractAdvislet

advisletMetadata, advisor, parametersMap

Fields inherited from interface com.bea.p13n.advisor.AdviceRequestConstants

CATALOG_QUERY_WRAPPER, CONTENT_APPEND_QUERY_STRING, CONTENT_MANAGER, CONTENT_MANAGER_HOME, CONTENT_QUERY_CONTEXT_PARAMS, CONTENT_QUERY_MAX_ITEMS, CONTENT_QUERY_NODE, CONTENT_QUERY_SORT_BY, CONTENT_QUERY_STRING, CONTENT_SEARCH_PATHS, DATE, HTTP_REQUEST, HTTP_SESSION, NOW, RULES_FILTER_CLASS, RULES_FILTER_CLASS_NAME, RULES_INPUT_OBJECTS, RULES_RULENAME_TO_FIRE, RULES_RULESET_NAME, SHOPPING_CART, TIME, TIME_INSTANT, USER

Fields inherited from interface com.bea.p13n.advisor.AdviceConstants

RESULTS

Constructor Summary

RulesAdvisletImpl(Advisor advisor, Metadata metadata)
Construct an instance of this object and bind it to its Advisor and Metadata instances.

Method Summary

protected void	addResults(Advice advice, Iterator iterator) Adds the contents of a given iterator to a given advice.
Advice	getAdvice(AdviceRequest request) Executes an AdviceRequest and returns the Advice object.s
protected Object[]	getInputObjects(Advice advice, AdviceRequest request) Returns the input objects for a given advice and advice request.
protected ObjectFilter	getObjectFilter(Advice advice, AdviceRequest request) Returns the object filter for a given advice and advice request.
Object[]	getRequiredAttributes() Returns an array of required attributes for the advislet.
protected String	getRuleNameToFire(Advice advice, AdviceRequest request) Returns the name of the rule that must be fired for a given advice and advice request.
protected String	getRuleSetName(Advice advice, AdviceRequest request) Returns the rule set name for the given advice and advice request.
protected RulesManager	getRulesManager(Advice advice, AdviceRequest request) Returns a RulesManager instance for a given advice and advice request.
boolean	initialize(Map parameters, Object parameterDocument) Initialize this instance from its XML configuration environment.
protected void	sendRuleEvent(AdviceRequest request, Advice advice) Generates a rule event for tracking listeners.
protected AdviceRequest	setupRequest(Advice advice, AdviceRequest request) Sets up a given advice request.

Methods inherited from class com.bea.p13n.advisor.AbstractAdvislet

getAdvisor, getMetadata, toString, validateAdviceRequest

Methods inherited from class java.lang.Object

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

Field Detail

IGNORE_RULE_NAME

public static final String IGNORE_RULE_NAME

The key name for the optional ignore rule name parameter.

See Also:

Constant Field Values

IGNORE_RULESET_NOT_FOUND

public static final String IGNORE_RULESET_NOT_FOUND

The key name for the optional ignore rule name parameter.

See Also:

Constant Field Values

RULESET_NAME

public static final String RULESET_NAME

The key name for the optional rule set name parameter.

See Also:

Constant Field Values

Constructor Detail

RulesAdvisletImpl

public RulesAdvisletImpl(Advisor advisor,
                         Metadata metadata)

Construct an instance of this object and bind it to its Advisor and Metadata instances.

Method Detail

addResults

protected void addResults(Advice advice,
                          Iterator iterator)
                   throws AdvisorException

Adds the contents of a given iterator to a given advice.

Parameters:

advice - The target advice.

iterator - The source iterator.

Throws:

AdvisorException - On general Advisor exception.

getAdvice

public Advice getAdvice(AdviceRequest request)
                 throws IllegalArgumentException,
                        AdvisorException

Executes an AdviceRequest and returns the Advice object.s

Specified by:

getAdvice in interface Advislet

Overrides:

getAdvice in class AbstractAdvislet

Parameters:

request - the AdviceRequest containing the paramters for the request

Returns:

the Advice instance with the result of the Advisor.getAdvice call.

Throws:

IllegalArgumentException

AdvisorException

getInputObjects

protected Object[] getInputObjects(Advice advice,
                                   AdviceRequest request)

Returns the input objects for a given advice and advice request.

Parameters:

advice - The target advice.

request - The target request.

Returns:

The input objects.

getObjectFilter

protected ObjectFilter getObjectFilter(Advice advice,
                                       AdviceRequest request)
                                throws AdvisorException

Returns the object filter for a given advice and advice request.

Parameters:

advice - The current advice.

request - The current advice request.

Returns:

The object filter.

Throws:

AdvisorException - On general Advisor exception.

getRequiredAttributes

public Object[] getRequiredAttributes()

Description copied from interface: Advislet

Returns an array of required attributes for the advislet. The array contains pairs of items: even items are attribute names while odd items are the Class for the item. This information is used by the Advisor to ensure Advislets are not invoked with invalid parameters. Overide the validateAdviceRequest method to perform additional processing above and beyond attribute type checking.

Specified by:

getRequiredAttributes in interface Advislet

Overrides:

getRequiredAttributes in class AbstractAdvislet

getRuleNameToFire

protected String getRuleNameToFire(Advice advice,
                                   AdviceRequest request)
                            throws AdvisorException

Returns the name of the rule that must be fired for a given advice and advice request.

Parameters:

advice - The current advice.

request - The current advice request.

Returns:

The rule name.

Throws:

AdvisorException - On general Advisor exception.

getRuleSetName

protected String getRuleSetName(Advice advice,
                                AdviceRequest request)
                         throws AdvisorException

Returns the rule set name for the given advice and advice request.

Parameters:

advice - The current advice.

request - The current advice request.

Returns:

The rule set name.

Throws:

AdvisorException - On general Advisor exception.

getRulesManager

protected RulesManager getRulesManager(Advice advice,
                                       AdviceRequest request)
                                throws AdvisorException

Returns a RulesManager instance for a given advice and advice request.

Parameters:

advice - The current advice.

request - The current advice request.

Throws:

AdvisorException - On general Advisor exception.

initialize

public boolean initialize(Map parameters,
                          Object parameterDocument)
                   throws AdvisorException

Initialize this instance from its XML configuration environment.

Specified by:

initialize in interface AdvisletChainElement

Overrides:

initialize in class AbstractAdvislet

Parameters:

parameterDocument - the XML Document node for the configuration environment

parameters - A map containing key-value pairs.

Returns:

true if required initialization parameters were present.

Throws:

AdvisorException - If an error occurs during initialization process.

sendRuleEvent

protected void sendRuleEvent(AdviceRequest request,
                             Advice advice)

Generates a rule event for tracking listeners.

Parameters:

request - The current advice request.

advice - The current advice.

setupRequest

protected AdviceRequest setupRequest(Advice advice,
                                     AdviceRequest request)
                              throws AdvisorException

Sets up a given advice request.

Parameters:

advice - The current advice.

request - The current advice request.

Returns:

The initialized advice request.

Throws:

AdvisorException - On general Advisor exception.