[:].isEmpty() triggers the wrath of the sandbox.
PR #183
PR up at https://github.com/jenkinsci/script-security-plugin/pull/183
Code changed in jenkins User: Andrew Bayer Path: src/main/resources/org/jenkinsci/plugins/scriptsecurity/sandbox/whitelists/generic-whitelist http://jenkins-ci.org/commit/script-security-plugin/7a76cd1753c4f02850194ab06824a5d4e8a4b9f5 Log: [FIXED JENKINS-49542] Whitelist Map#isEmpty()
Merged, will be included in the next script-security release (which should be 1.42).
PR up at https://github.com/jenkinsci/script-security-plugin/pull/183