public Date getLockedDate() {
        return new Date(lockedTime);
    }
Returns the date when the room was locked. Initially when the room is created it is locked so
the locked date is the creation date of the room. Afterwards, the room may be manually
locked and unlocked so the locked date may be in these cases different from the creation
date. When the room is unlocked a Date with time 0 is returned.

@return the date when the room was locked.
xmppserver/src/main/java/org/jivesoftware/openfire/muc/MUCRoom.java