Error "Unable to load FastStringService" when running jsonSlurper.parseText

Hello,

I use this code :

String jiraParamsFile = new File(‘/appli/confluence-shared-home/script/JiraIhmRESTParams.json’).text
def jsonSlurper = new JsonSlurper()
def jiraRootParams
jiraRootParams = jsonSlurper.parseText(jiraParamsFile) as Map;

And I have the error message “Unable to load FastStringService” on the line :
jiraRootParams = jsonSlurper.parseText(jiraParamsFile) as Map

The content of jiraParamsFile is :
{“NbKeysJiraIhmParams” : 1, “JiraIhmProjectParams” : { “JiraRESTCurlUrl” : “https://jira-dev.hpr.f.bbg” } }

Does anyone have any idea what to fix ?

I am looking forward to your reply.

Best regards.

Philippe C.