1. A method for discrete event simulation model of a system utilizing just-in-time compilation for at least one code block associated with at least one event in the discrete event simulation model, the method comprising the steps of: (a) determining the at least one event in a discrete event simulation model according to a kind of the at least one event; (b) retrieving the at least one code block associated with the at least one event; (c) compiling the at least one code block into an object file (OBJ) using a compiler; (d) linking the object file with at least one predetermined function in a simulation library (LIB); (e) compiling the object file and the at least one predetermined function into a customized dynamic link library (DLL); (f) loading the customized dynamic link library within a discrete event simulation program execution; (g) linking the customized dynamic link library to a simulation program associated to the system; (h) executing at least one user-entered logic in high speed by integrating a just-in-time compiler embedded into the simulation model to allow dynamic generation of high speed code blocks associated with the at least one event.