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Page Remove in activity causing null pointer exception



Null pointer Exception is thrown on page-remove of page-list property .
This occurs only when reference properties are present and Same class property value is set from declare expression. This is combination of Reference property, Declare Expression

Error Messages


Steps to Reproduce

Define a Data class ( say products )  and declare some propeties in that class.
Update a property say ProductName as reference property
Create a Productd Pagelist property in class  PegaSample
Define a delcareexpression for ProductID in Products class.
Define a TempProperty in PegaSample.
Create a Simple flow with 2 or 3 assignments
Call sample activity say SetProduct activity as a Pre-activity in first flow action to create products page
Create Products list page in SetProduct Activity.
Call another sample activity say, updateProduct activity as a Pre-activity in second flow action to remove Product page.
Do a page-remove for Products page list in UpdateProduct activity
Run the Flow and submit first assignment and check the clipboard.
And also declate expression has set the value for ProductID property with the value of py Label.
 Submit second flow action and we can see Nullpointer exception.
This occurs only when any property value in Product class is set using Declare Expression.

Root Cause

The root cause of this problem is a defect in Pegasystems’ code/rules. Basically the order of the api calls setParent(null) and trackDeletion were not correct.


This issue is resolved by hotfix item : HFIX-21884
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Published June 12, 2015 - Updated October 8, 2020

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