SOAP Handler server side

My question is when to use server side handler and when to use client side handler. I have searched google which says that for server side handler we user annotation @Handler on jax-ws service and for implementing of client side handler, we make that in code itself, not by annotation and XML file.

For example, I have a web service which clients consume by inputting SOAP envelope in SOAPUI and then invoking my service and my service inserts in database. Shall I implement server side handler in it or client-side ?