MockPart part2 = new MockPart("requestPart2", "Hello World 2".getBytes());
MockHttpServletRequest request = new MockHttpServletRequest();
request.setMethod("POST");
request.setContentType("multipart/form-data");
request.addPart(part1);
request.addPart(part2);
webRequest = new ServletWebRequest(request);
Object result = resolver.resolveArgument(paramPartArray, null, webRequest, null);
assertTrue(result instanceof Part[]);