Cusomizing Guest OS of exising Window VM for setting new network configuration using Customization Spec using VIM java apis.

I am trying to customize guest OS of existing Windows VM for setting new network configuration IP address etc using customization Spec using VIM java apis. I am not finding any example code for doing this for existing Windows VM . Mostly examples are of customization during clone/deploy . I want to do this for already existing Windows VM . Can somebody confirm this that it is possible and if yes point me to the sample code for doing this for existing windows VM ?

Thanks in advance.

-Deep