Binding binding = control.createMock(Binding.class);
expect(binding.getHandlerChain()).andReturn(list).anyTimes();
SoapMessage message = control.createMock(SoapMessage.class);
Exchange exchange = control.createMock(Exchange.class);
expect(message.getExchange()).andReturn(exchange).anyTimes();
expect(message.keySet()).andReturn(new HashSet<String>());
expect(exchange.get(HandlerChainInvoker.class)).andReturn(invoker);
control.replay();
SOAPHandlerInterceptor li = new SOAPHandlerInterceptor(binding);
Set<QName> understood = li.getUnderstoodHeaders();