code: @Test public void shouldAssumeResourceChangedWhenModifiedSinceHeaderExtractionFails() throws Exception {
    final String resourceUri="classpath:" + packagePath + "/"+ "test.css";
    when(mockAuthorizationManager.isAuthorized(resourceUri)).thenReturn(true);
    when(request.getParameter(ResourceProxyRequestHandler.PARAM_RESOURCE_ID)).thenReturn(resourceUri);
    when(request.getDateHeader(HttpHeader.IF_MODIFIED_SINCE.toString())).thenThrow(new IllegalArgumentException("BOOM!"));
    victim.handle(request,response);
    verify(response).setStatus(HttpServletResponse.SC_OK);
  }
  