// Create a standard Jackson mapper object
ObjectMapper mapper = new ObjectMapper();
SimpleModule module = new SimpleModule("CleverModule", Version.unknownVersion());
module.addDeserializer(District.class, new DistrictDeserializer());
module.addDeserializer(School.class, new SchoolDeserializer());
module.addDeserializer(Teacher.class, new TeacherDeserializer());
module.addDeserializer(Student.class, new StudentDeserializer());
mapper.registerModule(module);