assertEquals(new String(file2.getBytes()), new String(mtb1.getField2())); MultipartTestBean2 mtb2 = new MultipartTestBean2(); assertArrayEquals(null, mtb2.getField1()); assertEquals(null, mtb2.getField2()); binder = new ServletRequestDataBinder(mtb2, "mybean"); binder.registerCustomEditor(String.class, "field1", new StringMultipartFileEditor()); binder.registerCustomEditor(String.class, "field2", new StringMultipartFileEditor("UTF-16")); binder.bind(request); assertEquals(new String(file1a.getBytes()), mtb2.getField1()[0]); assertEquals(new String(file1b.getBytes()), mtb2.getField1()[1]); assertEquals(new String(file2.getBytes(), "UTF-16"), mtb2.getField2()); request = resolver.resolveMultipart(originalRequest); binder.setBindEmptyMultipartFiles(false); String firstBound = mtb2.getField2(); binder.bind(request); assertFalse(mtb2.getField2().isEmpty()); assertEquals(firstBound, mtb2.getField2()); assertTrue(mtb2.getField2().isEmpty());