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Data page giving - java.util.ConcurrentModificationException



ConcurrentModificationException occurs when executing a datapage standalone. This occurs sporadically. The datapage is sourced from a LookUp of a class.

Error Messages

Exception java.util.ConcurrentModificationException: null  at java.util.HashMap$HashIterator.nextNode( ~[?:1.8.0_171]
 at java.util.HashMap$ ~[?:1.8.0_171]
 at ~[prprivate.jar:?]
 at com.pega.pegarules.exec.internal.declare.infengine.pages.DeclarativePageInstanceImpl.getReduxPage( ~[prprivate.jar:?]

Steps to Reproduce

  1. Create a casetype with a single assignment.
  2. Create a case of Step 1 casetype.
  3. Create a datapage at the thread level with  the Edit Mode as 'Read Only'.
  4. Pass a case ID as a parameter to configure a LookUp of class (of Step 1 casetype) as data source.

Root Cause

A defect in Pegasystems’ code or rules.


Update to Pega Platform 8.1.7.
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Published November 1, 2019 - Updated December 2, 2021

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