@Test
public void testSetExceptionCode_exception_code_is_notnull() {

    FlashMap flashMap = new FlashMap();
    mockRequest.setAttribute(DispatcherServlet.OUTPUT_FLASH_MAP_ATTRIBUTE,
            flashMap);
    SystemException occurException = new SystemException("code001", "message");
    testTarget.setExceptionCode(occurException, mockRequest, mockResponse);
    assertThat(mockRequest.getAttribute("exceptionCode").toString(), is(
            "code001"));
    assertThat(mockResponse.getHeader("X-Exception-Code"), is("code001"));
    assertThat((String) flashMap.get("exceptionCode"), is("code001"));
}