Mapping Functions

Mappings are small functions that allow to modify a value into another value when it meets certain conditions.
These functions are not part of the page, they need to be declared outside of it.
Similar to the NLS objects, their scope is limited to the file where they are declared.
We can use the import instruction to import a file that contains many Mappings. Like that they can be declared once and used in many pages.

The default project includes some mappings in the file :
ProjectFolder/webportal/pages/resources/mappings.page.
Those mappings are ready to use and can be imported in any page. See the list of examples for more detail.

Mappings can be used with the Transform keyword. As a best practice, the return value of mapping should use the according NLS.

Transform variable using mappingIdentifier.

There are several kind of mappings depending of the type of variable.

To modify string values. Syntax:

mappingIdentifier = StringMapping {
    when "value1" then $nls.value
    otherwise current
}

When the received variable matches "value1" it will change it to use the NLS value $nls.value. Otherwise , value will not be changed.

To modify boolean values. Syntax:

mappingIdentifier = BooleanMapping {
    when True then $nls.value
    when False then $nls.value2
}

To modify Integer values. Syntax:

mappingIdentifier = IntMapping {
    when InvalidInteger then 0
    when >10 then 10
    otherwise current
}

If the value is invalid then it will return 0, if its greater than 10 it will return 10. In any other case, the value will not be changed.

To retrieve a string based on a date condition. Syntax:

tooLateMapping = DateMapping {
 when DateAfter current then "too late"
 otherwise "ok"
}

If the given date if after the current date/time, returns "too late", otherwise returns "ok".
Allowed conditions are DateAfter, DateBefore, DateBetween, Not, TimeAfter, TimeBefore, TimeBetween.

Some of the examples of mapping provided with the default project:

optionStringMapping = StringMapping {
 when IsEmpty then $global.novalue
 otherwise current
}

This very useful mapping will return an "No Value" when a string is empty. Like that we don't see "Null" in the page.

reconciliationStatusMapping = StringMapping {
  when "orphan" then $reconciliation.status.orphan
  when "reconciled" then $reconciliation.status.reconciled
  when "leave" then $reconciliation.status.leave
  when "noowner" then $reconciliation.status.noowner
  otherwise current
}

This mapping will transform the reconciliation code into a user-friendly value using NLS.

nullToZeroMapping = IntMapping {
 when InvalidInteger then 0
 otherwise current
}

If the value of the integer is invalid, then it will be set to 0, this will avoid "Null" values