add source generalization
extract to superclass
extract writeField to super class
'inline constants value
abstract class and method
extract writeBody
extract write to superclass
extract writeBody and getSize to superclass
check NPE
refactor centralunit
add server.java class
check args usage
build config server
extract readEmailListFile
extract store session
add conditional src
obvious conditional
format code
add src pointofsale for error handling and logging session
test inventory