Hi Isomorphic,
please see this thread and there especially #2 (v12.0p_2020-04-12).
If you run countryList.data.fetchOperation in the Developer Console's evaluate box, you'll get this result:
This is clearly not a simple string, as the docs says:

In SmartGWT this leads to this exception:
Best regards
Blama
please see this thread and there especially #2 (v12.0p_2020-04-12).
If you run countryList.data.fetchOperation in the Developer Console's evaluate box, you'll get this result:
Code:
Evaluator: result of 'countryList.data.fetchOperation' (0ms):
{ID: "fetchFooBar",
dataSource: "worldDSExport",
type: "fetch",
filterType: "paged",
loadDataOnDemand: true}
In SmartGWT this leads to this exception:
Code:
Caused by: java.lang.ClassCastException: com.google.gwt.core.client.JavaScriptObject$ cannot be cast to java.lang.String
at com.smartgwt.client.core.BaseClass.getAttributeAsString(BaseClass.java)
at com.smartgwt.client.data.ResultSet.getFetchOperation(ResultSet.java:503)
Blama
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