Jackson #Deserializer doesn't work - jackson

Question

This is a duplicated question of this
POJO
#Entity
#Table(name = "pet")
public class Pet {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long petId;
private String petName;
private Date birthday;
#JsonSerialize(using = Serializer.class)
public Date getBirthday() {
return birthday;
}
#JsonDeserialize(using = Deserializer.class)
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public Long getPetId() {
return petId;
}
public void setPetId(Long petId) {
this.petId = petId;
}
public String getPetName() {
return petName;
}
public void setPetName(String petName) {
this.petName = petName;
}
}
Serializer
public class Serializer extends JsonSerializer<Date> {
#Override
public void serialize(Date date, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException, JsonProcessingException {
System.out.println("Serializer");
}
}
Deserializer
public class Deserializer extends JsonDeserializer<Date> {
#Override
public Date deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException, JsonProcessingException {
System.out.println("Deserializer works.");
return new Date();
}
}
Maven Dependency
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.3.2</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.3.2</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.3.2</version>
</dependency>
update: controller code
#Transactional
#Controller
public class Demo {
#Resource
private Dao dao;
#ResponseBody
#RequestMapping("/test")
public String tester(Pet pet){
dao.saveOrUpdate(pet);
return "success";
}
#ResponseBody
#RequestMapping("/test2")
public List<Pet> tester2(){
List<Pet> pets = dao.query(Pet.class);
return pets;
}
}
however only Serializer will be invoked everytime, Deserializer doesn't take any effect, I can't see where is wrong, could anybody help me?
Thanks.