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RuntimeException: caught exception while expanding property



Post upgrading Pega Platform 7.2 to Pega Platform 8.2.2, error occurs and user is unable to open work objects.

Error Messages

property .pyXMLRootNode was expected to have a List or Page mode, but attributes are @Z:J?N:. Details: Invalid value for aAttr passed to, String, char, StorageStream, List) java.lang.RuntimeException: caught exception while expanding property pyXMLRootNode on page pyWorkPage.pxFlow(MonitorDefendant).pyFlowParameters at at at at at at at at at at at at at at at at at

Steps to Reproduce

Open the work object.

Root Cause

After searching the code references for pyXMLRootNode, it is determined that the property is created in the Parameter page in the invokeXMLParseRule method in the ParseRuleUtils class. These properties are not removed after the Parse XML rule is invoked. Hence, the created parameters are passed to the work object flow because the 'Pass current Parameter page' checkbox is enabled during the REST/SOAP connector call in an activity.
Therefore, the parameters created during the Parse XML rule execution are added to the pxFlow page of the work object. As a result, the work object cannot be opened, since the ClipboardAPI failed to deserialize the data available in these parameters (that is, pyXMLRootNode, apacheXMLDSigProvider, and pyRequestParams).


Perform either of the following local-changes:
  • Pass the required parameters in the fields instead of enabling the 'Pass current parameter page' checkbox in the REST connector call.
  • Override the pyFlowParameters property in to an unlocked ruleset.
  • Disable the 'Validate Embedded pages' checkbox in the Advanced tab.
This works for work objects that are created/updated in Pega Platform 8.x. However, the issue still persists for migrated work objects which are not yet updated in Pega Platform 8.x.

Perform the below local-change for untouched migrated work objects:
  1. Apply HFix-58767.
  2. Set the Dynamic System Setting (DSS) to skip the exception while opening the work object due to the problematic properties.

    Set propertiesToIgnoreDuringBlobDeserialization DSS to pyXMLRootNode apacheXMLDSigProvider

  3. Restart the Application server.
  4. Use the Obj- methods to write a utility to open the work object and remove the problematic properties.

    While opening the work object, the below error is generated in the log.

    ERROR - Exception caught during deserialization of Java Object value of property .pyXMLRootNode.  Message: Inconsistent vector internals         Inconsistent vector internals
                    at java.util.Vector.readObject( ~[?:1.8.0_171]
                    at sun.reflect.GeneratedMethodAccessor489.invoke(Unknown Source) ~[?:?]
                    at sun.reflect.DelegatingMethodAccessorImpl.invoke( ~[?:1.8.0_171]
                    at java.lang.reflect.Method.invoke( ~[?:1.8.0_171]
                    at ~[?:1.8.0_171]
                    at ~[?:1.8.0_171]

    The error occurs because the system is unable to deserialize the content available in these problematic properties in the corrupted work objects. However, the utility executes successfully, and the properties can be removed from the work object.

Published July 18, 2020 - Updated December 2, 2021

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