The

Developer’s Setup Guide

for the VMware vSphere WS SDK has a chapter describing how to set up your programming environment for Java.

The

Programming Guide

for the vSphere SDK contains some sample code written in Java, and based on the JAX-WS development framework.

ESXi hosts and the VMware vSphere WS API use a programming model based on Web services, in which clients generate Web services description language (WSDL) requests that pass over the network as XML messages encapsulated in simple object access protocol (SOAP). On ESXi hosts or vCenter Server, the vSphere layer answers client requests, usually passing back SOAP responses. This is a different programming model than the object-oriented function-call interface of C++ and the VIX API.