Client JWAVE Java programs communicate with PV‑WAVE through a PV‑WAVE function called a JWAVE wrapper. A JWAVE wrapper function is a PV‑WAVE function that contains some specific JWAVE API calls. These JWAVE-specific functions are included in the dynamically loaded JWAVE library; therefore, to the JWAVE developer, these functions can be used just like any PV‑WAVE function.

Typically, a JWAVE wrapper function is used as an interface between the JWAVE client and one or more PV‑WAVE applications. The JWAVE wrapper receives parameters from the client, processes those parameters in some manner, and returns information back to the client. The returned information can be numeric or string values (except complex numbers), including scalars and arrays. The server can also return graphics to the client if PV‑WAVE graphics commands were used in the JWAVE wrapper.