.item:
Color Boblight <colorwheel></colorwheel>

.rules

 import org.openhab.core.library.types.* 
 var HSBType hsbValue 
 var String red 
 var String green 
 var String blue 
 var String hexValue 
 rule "Boblight" when Item Boblight changed then
     executeCommandLine('/usr/bin/killall@@boblight-constant') 
     hsbValue = Boblight.state as HSBType 
     red = Integer::toHexString(hsbValue.red.intValue)
     green = Integer::toHexString(hsbValue.green.intValue) 
     blue = Integer::toHexString(hsbValue.blue.intValue) 
     hexValue = ("00"+red).substring(red.length()) + ("00"+green).substring(green.length()) + ("00"+blue).substring(blue.length()); 
     if (!hexValue.equals("000000")) { 
         logInfo( "FILE", hexValue ) 
         executeCommandLine('/usr/bin/boblight-constant@@-p@@0@@-f@@-s@@172.16.40.132@@' + hexValue) }
    end

UPDATE:

 var HSBType hsbValue 
 var String red 
 var String green 
 var String blue 
 var String hexValue 
 rule "lsBoblight" when Item lsBoblight received command then { 
 Boblight.sendCommand(switch receivedCommand { 
     case 1 : "0,0,100" 
     case 2 : "0,100,100" 
     case 3 : "60,100,100" 
     case 4 : "120,100,100" 
     case 5 : "120,100,50" 
     case 6 : "180,100,100" 
     case 7 : "240,100,100" 
     case 8 : "300,100,100" 
     default : "0,0,0" }) } 
 end 
 
 rule "Boblight" when Item Boblight changed then 
     executeCommandLine('/usr/bin/killall@@boblight-constant')
     hsbValue = Boblight.state as HSBType
     red = Integer::toHexString(hsbValue.red.intValue)
     green = Integer::toHexString(hsbValue.green.intValue)
     blue = Integer::toHexString(hsbValue.blue.intValue)
     hexValue = ("00"+red).substring(red.length()) + ("00"+green).substring(green.length()) + ("00"+blue).substring(blue.length()); 
     if (!hexValue.equals("000000")) { 
         executeCommandLine('/usr/bin/boblight-constant@@-p@@255@@-f@@-s@@172.16.40.132@@' + hexValue) 
     } else { 
         lsBoblight.sendCommand(0) 
     } 
 end