### Question:
SlingMultipartResolver implements MultipartResolver { @Override @Nonnull public MultipartHttpServletRequest resolveMultipart(@Nonnull HttpServletRequest request) throws MultipartException { if (request == null) { throw new IllegalArgumentException("Method argument request must not be null."); } if (!(request instanceof SlingHttpServletRequest)) { throw new IllegalArgumentException("Method argument request must be a " + SlingHttpServletRequest.class + ", but is a " + request.getClass() + "."); } return new MultipartSlingHttpServletRequest((SlingHttpServletRequest) request); }  @Override boolean isMultipart(@Nonnull HttpServletRequest request); @Override @Nonnull MultipartHttpServletRequest resolveMultipart(@Nonnull HttpServletRequest request); @Override void cleanupMultipart(@Nonnull MultipartHttpServletRequest request);  }### Answer:
@Test(expected = IllegalArgumentException.class) public void testResolveMultipartWithNullValue() { testee.resolveMultipart(null); }