HashMap<String, Object> extraContext = new HashMap<String, Object>();
extraContext.put(ActionContext.PARAMETERS, params);
ActionProxy proxy = actionProxyFactory.createActionProxy("", MockConfigurationProvider.PARAM_INTERCEPTOR_ACTION_NAME, extraContext);
ActionConfig config = configuration.getRuntimeConfiguration().getActionConfig("", MockConfigurationProvider.PARAM_INTERCEPTOR_ACTION_NAME);
ParametersInterceptor pi =(ParametersInterceptor) config.getInterceptors().get(0).getInterceptor();
pi.setAcceptParamNames("blah, baz");
proxy.execute();
SimpleAction action = (SimpleAction) proxy.getAction();