cell.cross returns Error: “java.lang.NullPointerException”

[magdmartin]

I am creating this issue to track in Github the error reported in conversation on the forum https://forum.openrefine.org/t/cell-cross-not-working-getting-the-following-error-message-error-java-lang-nullpointerexception/688 - I am not personally experiencing the issue and cannot help to reproduce it.

Summarizing the environment from the four users that reported issues we have no clear pattern:

• OpenRefine 3.7.1 and 3.7.2 - macOS Ventura Opera 97.0.4 - archilecteur
• OpenRefie version unknown Mac Os version 13.6.2 Java(TM) SE Runtime Environment (build 17.0.9+11-LTS-201) Bart_Magnus
• OpenRefine 3.7.9 ubuntu Java version "21.0.2" 2024-01-16 LTS Michel_Guenard
• OpenRefine 3.7.5 and 3.7.9 Windows 11 openjdk version "17.0.10" 2024-01-16 Michael_Beckett

Current Results

The cell.cross function returns a NullPointerException

[tfmorris]

This is caused by corrupt workspaces which have projects listed in workspace.json which don't have project directories. Although we have code to attempt to recover a metadata.json file if it's missing and there's data there, if there's nothing at all, it will cause problems for the project lookup by name that cross() uses.

One way to identify workspaces that might be corrupted in this way is empty project directories in the workspace directory. If they are deleted, they will get recreated the next time OpenRefine is started. Editing the workspace.json file to remove the offending project ID(s) (there may be more than one) is a temporary workaround until a fixed version of OpenRefine is available.