Constructing Non-Persistent Dynamic Rules › Non-Persistent Dynamic Decision Tables

Non-Persistent Dynamic Decision Tables

The NPDRules example in the \Examples\DynaRule\NPDRule directory serves as the basis of following explanation of non-persistent dynamic decision tables. In NPDRules, the following classes and methods fulfill the facilities that are required to create non-persistent dynamic rules.

Note: For more information about these facilities, see Facilities for Constructing Non-Persistent Dynamic Rules.

• A class that implements the DecisionTableRule_Defn_Interface interface.

  In NPDRules, this class is Sample_DTbl_Definer.

  Note: For more information about constructing an implementation of this interface, see Non-Persistent Rule Definer Class.

  The Sample_DTbl_Definer class can serve as a typical model for defining such classes, although other ways of implementing the methods of DecisionTableRule_Defn_Interface are possible. The functionality of Sample_Dtbl_Definer is completely general, and it may be used in other applications just as it is implemented here.

• Mechanisms to define the condition and action values and to hold the association of these values with the domain interface members of the non-persistent rule.

  In NPDRules, these mechanisms are provided by the ConditionData and ActionData classes. Interface methods implemented in Sample_Dtbl_Definer made reference to instances of these structures to obtain the values of conditions and actions of the dynamic rule.

  Although other application strategies are possible for defining the required mechanisms, these classes are also completely general and can be reused in other applications just as they are implemented in NPDRules.

• An agent that constructs and posts the non-persistent rules.

  In NPDRules, this agent is the Examples class. In its PostDTbl( ) method, the Examples class:

  1. Creates the domain interface members that are referenced by the non-persistent decision table being constructed.
  2. Specifies the condition and action values for each domain interface member and associates these values with the appropriate domain interface member
  3. Posts the decision table.

  PostDTbl( ) invokes the _DefineDTblConditions( ) and _DefineDTBlActions( ) methods. These methods construct the instances of the ConditionData and ActionData classes that define the condition and action values for the methods referenced by the non-persistent decision table. These methods contain highly domain specific content.

  Note: For more information, see Constructing Decision Table Conditions and Constructing Decision Table Actions. For more information about posting the decision table that has now been constructed, see Posting a Non-Persistent Decision Table.