The main function of this plugin is to set certain worlds as controlled, which will not be accessible unless the player have the corresponding permission. After you set a world controlled, the players have the permission "nworldpermissions.forfreeto.<world_name>" will get teleported and receive a message: And if the player doesn't have such a permission: All the messages are customizable.
This plugin also provides the ability to teleport all the players out of a world (including the offline ones).
By using this plugin, you can solve those problems:
A world has been reset, and I'd like to build something first, how to temporarily prevent players from entering?
When a world is going to be reset, how to teleport the players out of that world?