Change integer multiplication to long multiplication
Refine toString() switch
Make "instance" field volatile
Add serialVersionUIDs to Serializables
Check if "connection" is null
Check if "keys" is null
Remove local "logger" field
Check if messages have been loaded
Do not checking if backup directory has been created

It failed when the directory already existed
Refine LogItCommand
Set maximum number of params for "backup restore" to 1 instead of 0
Get some messages fixed and parameters added