### Question:
JsonUtils { public static String toJsonStringWithDefaultPrettyPrinter(Object obj) throws IOException { return WRITTER.writeValueAsString(obj); } private  JsonUtils(); static String toJsonStringWithDefaultPrettyPrinter(Object obj); static String toJsonString(Object obj); static List<?> toJsonList(String str, Class<?> elementType);  }### Answer:
@Test public void printObjectAsJson() throws IOException { OzoneQuota quota = OzoneQuota.parseQuota("123MB", 1000L); String result = JsonUtils.toJsonStringWithDefaultPrettyPrinter(quota); assertContains(result, "\"rawSize\" : 123"); assertContains(result, "\"unit\" : \"MB\""); assertContains(result, "\"quotaInCounts\" : 1000"); }