question: public boolean startUsingDataSocket ( ) { try { dataSocket = localDataSocket . onTransfer ( ) ; if ( dataSocket == null ) { Log . i ( TAG , "dataSocketFactory.onTransfer() returned null" ) ; return false ; } dataOutputStream = dataSocket . getOutputStream ( ) ; return true ; } catch ( IOException e ) { Log . i ( TAG , "IOException getting OutputStream for data socket" ) ; dataSocket = null ; return false ; } }
target:  Will be called by (e.g.) CmdSTOR, CmdRETR, CmdLIST, etc. when they are about to start actually doing IO over the data socket.