Problem (while developing)

When editing certain resource files (js / css) sometimes locks the files on windows requiring a restart, even if hot reloading should theoretically work.

problem reported and analysed in Forum (including a supposed patch):
http://forum.zkoss.org/question/110354/problems-encountered-while-deleting-resources-for-zk-spring-boot-project/

Places where UrlConnection.openConnection().getLastModified() is used in ZK:
https://github.com/zkoss/zk/search?q=getLastModified&unscoped_q=getLastModified

similar myfaces issue/patch reported here:
https://issues.apache.org/jira/browse/MYFACES-3888

older discussion on jboss: https://developer.jboss.org/thread/96782

Proposed

close the connections preventing this kind of lock or leak

Other Workarounds

https://www.eclipse.org/jetty/documentation/9.4.x/troubleshooting-locked-files-on-windows.html