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Data Transform form
Completing the Parameters tab

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Use the Parameters tab to identify any variables used as input parameters to the data transform's actions, or for output results.

Not every data transform uses parameters, and not every data transform action can use parameters. When the data transform is invoked, the system places parameter names and values on a nameless, classless page known as the parameter page, and noted by the prefix keyword param. For example, param.depth refers to the depth parameter.

The declared type of a parameter (such as Integer or String) indicates the format of a value. When evaluating expressions, the Pega 7 Platform follows the same casting and type conversion operations as for properties.

Parameter names are not properties, and are not defined by a property:

Add (Add a row) and complete rows of this array to define parameters for this data transform. To reference these parameters within the data transform actions on the Definition tab, use the keyword param followed by a period and the parameter name.

Field

Description

Name

Enter a name of your choice for the parameter. A parameter name must be a valid Java identifier. See How to enter a Java identifier.

Note: Do not use a name that starts with pz. Don't choose any of the reserved names. Don't choose a name that matches any of the system-supplied parameters.

Description

Enter a text description of this parameter, for information only. This text is used at design time for guiding use of the parameter when completing the Definition tab.

Data Type

Choose the type of data that is expected as the value for the parameter:

  • String — A Java string value
  • Boolean — A Boolean value
  • Integer — An integer value
  • Page Name — A page structure named on the Pages & Classes tab. If the parameter has Page Name for its Data Type, specify the parameter name and page class on the Pages & Classes tab.

The values for Boolean parameters are the same as Boolean properties:

  • The preferred values are the text constants "true" and "false"
  • The following are equivalent to "true": any non-zero numeric value (integer or double), the text constants "on", "yes", "t", or any value starting with a "y" in any case
  • Any other value corresponds to "false"
Required?

Choose Yes or No to indicate whether this parameter is required to have a non-null value when it is used in the data transform.

For a parameter with a Data Type of Boolean, the false value is sometimes correctly indicated by a blank or null value. Don't choose Yes in this field for a Boolean parameter, because a form may return a blank value for "false", which may be considered a missing property.

Note: Do not select Required? for an Out parameter (a parameter where In/Out is set to Out).

In/Out

Select In or Out to indicate whether the parameter is used for input to this data transform or output from this data transform.

Caution: The system does not prevent this data transform from setting the value of a parameter specified as In. A data transform that is invoked from another rule (for example, in the Apply Data Transform action used in another data transform or in the Apply-DataTransform method used in an activity) can access and change both In and Out parameters on the parameter page.

Default Value

Optional. You can enter a literal constant value that appears as the default parameter value when the system presents a parameter prompt form to a user invoking this data transform. For example, when this data transform is used in an Apply Data Transform action in another data transform, the user can bring up a window in which to specify the input parameter values. That window displays these default values.

SmartPrompt Type

Optional. For some parameters, you can configure SmartPrompt facilities to list a set of values for the parameter that a person can choose from when specifying the parameter values.

The values listed by SmartPrompt must be a key part to a concrete class with one to three key parts.

To enable SmartPrompt operation, enter a class name here (such as Rule-Obj-FieldValue or Data-Party-Gov) to create a configuration that, at runtime, allows a user to enter this parameter using SmartPrompt.

Validate As

Optional. Identify a property that further qualifies the SmartPrompt operation.

If you selected Rule-Obj-FieldValue in the SmartPrompt Rule field, enter here the second key part of the field value rules to appear at runtime in SmartPrompt lists.

If you selected another class in the SmartPrompt Rule field, identify a property that is a key part of the indicated class, if the class key contains more than one key part.

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