Can java service implement a function as same as vSphere web client default function?

Hi, I just want to know, can we use java service to implement a function like create/edit/remove datacenter, host, vm?

for example(host).

Create a custom action in cluster drop down list called "Create host", then pop up our custom UI(maybe add some additional options, click finish after fill in all required options, then call our java service to achieve create host function as default function in vsphere web client, and also execute for our additional options.