It looks like
https://issues.jboss.org/browse/JBDS-2635, it happens randomly under
Windows. As a workaround I would suggest to install Bring Your Own Eclipse JBoss Developer
Studio as it is explained here
(
https://access.redhat.com/documentation/en-US/Red_Hat_JBoss_Developer_Stu...).
Posted by forums
Original post:
https://developer.jboss.org/message/920812#920812