Modifier delegate example

To illustrate, in the base PolicyCenter configuration, PolicyCenter provides a Modifier delegate. PolicyCenter stores the delegate definition in file Modifier.eti, in configuration > config > Metadata > Entity. The following is a simplified version of this definition file.

<?xml version="1.0"?>
<delegate xmlns="http://guidewire.com/datamodel"
          effdatedOnly="true"
          extendable="true"
          javaClass="com.guidewire.pc.domain.policy.Modifier"
          name="Modifier"
          requires="gw.api.domain.ModifierAdapter">
  <fulldescription><![CDATA[A list of states and their rating factors (e.g. experience modification 
          for workers' compensation).]]></fulldescription>
  <column desc="Boolean modifier"
          name="BooleanModifier"
          type="bit"/>
  ...
</delegate>

This delegate defines the following fields:

BooleanModifier
DateModifier
Eligible
Justification
PatternCode
RateModifier
ReferenceDateInternal
TypeKeyModifier
ValueFinal
State (type list)

Any entity that wants to use the Modifier delegate functionality must implement this delegate.

The modifier delegate extension

Suppose that you want to extend the definition of the Modifier entity in file Modifier.etx to add additional columns to the delegate entity. For example:

OverriddenRateModifier
SuggestedRateModifier

The delegate extension code looks similar to the following.

<extension
    xmlns="http://guidewire.com/datamodel"
    entityName="Modifier">
  <column
      desc="The rate modifier that has been overridden."
      name="OverriddenRateModifier"
      type="rate">
  </column>
  <column
      desc="The rate modifier that the external system has suggested."
      name="SuggestedRateModifier"
      type="rate">
  </column>
</extension>

These fields are then accessible to any entity that implements this delegate. You use these fields to support user overrides of the modifier rates originally suggested by an external process. All modifiers for all lines of business use this override process. Thus, by placing this functionality in the Modifier delegate, each entity that implements the Modifier delegate inherits this functionality, instead of each entity implementing this functionality separately.

Each line of business (LOB) uses one or two LOB-specific modifier entities that implement the Modifier delegate. For example:

BAModifier
BOPModifier
CPModifier
GLModifier
PAModifier
PAVehicleModifier
ProductModifier
WCModifier

Because each of these LOB-specific modifier entities already implements the Modifier entity, each automatically inherits the Modifier column extensions.

If an entity does not already implement the Modifier delegate, then you need to do one of the following:

If an extension for that entity already exists in the Extensions folder, then you need to modify that extension file so that it implements the required delegate. In this case, modify the extension entity and add the following, using the appropriate adapter name:
```
<implementsEntity adapter="xxx" name="Modifier"/>
```
If an extension for that entity does not exist in the Extensions folder, then you need to create an extension and have that entity extension implement the required delegate. In this case, right-click the extensions folder and select New > Other file. Enter the entity name and add the .etx extension. Populate the extension file with something similar to the following, using the appropriate adapter and entity name (entityName):
```
<?xml version="1.0"?>
<extension xmlns="http://guidewire.com/datamodel" entityName="xxx">
  <implementsEntity adapter="xxx" name="Modifier"/>
</extension>
```

Modifier delegates and arrays

Delegate entities do not support arrays, so the Modifier delegate does not include an array of RateFactor entities. Instead each concrete modifier type must define its own array of rate factors. Therefore, for each entity that implements the Modifier delegate (for example, BAModifier), there must also be a corresponding entity that implements the RateFactor delegate (for example, BARateFactor)

Modifier delegates and adapters

Each entity that implements the Modifier delegate must specify an adapter class. Each adapter class must implement the gw.api.domain.ModifierAdapter interface. This interface implements generic modifier operations such as returning the owning Modifiable entity and working with the array of rate factors.

Similarly, entities that implement the RateFactor delegate must separately specify an adapter class that implements the gw.api.domain.RateFactorAdapter interface. This adapter needs to define one method only, one that returns the owning Modifier.

To support out-of-sequence and preemption handling, each modifier type must implement its own matcher class. Each modifier and rate factor entity must separately implement the gw.api.effdate.MatchableEffDated interface. Guidewire provides the following classes as starting points for configuration:

gw.api.effdate.matcher.AbstractModifierMatcher.gs
gw.api.effdate.matcher.AbstractRateFactorMatcher.gs