Plugin Help Help to NPC command.

HI, i'm D.E.K.

To learning how to create plugins in Java.
I was wanting to create an RPG plugin (Equal Wynncraft , dream about it since I started ) . But I was wondering how to do it by command, example :

/npc-create <NPCName> <NPCEntityType>


I wanted to set the name of the NPC and the EntityType ( And the location, but I know to do this) by his command , except that I can not (I tried a number of ways in arguments , as always, errors) . :v
( I am an intermediary in Java) .


NOTE: I'm on another PC, so I can not catch the Code of my Eclipse.