Annotazioni Jackson - @JsonDeserialize
@JsonDeserialize viene utilizzato per specificare un deserializzatore personalizzato per annullare il marshalling dell'oggetto json.
Esempio @JsonDeserialize
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
public class JacksonTester {
public static void main(String args[]) throws ParseException{
ObjectMapper mapper = new ObjectMapper();
String jsonString = "{\"name\":\"Mark\",\"dateOfBirth\":\"20-12-1984\"}";
try {
Student student = mapper
.readerFor(Student.class)
.readValue(jsonString);
System.out.println(student.dateOfBirth);
}
catch (IOException e) {
e.printStackTrace();
}
}
}
class Student {
public String name;
@JsonDeserialize(using = CustomDateDeserializer.class)
public Date dateOfBirth;
}
class CustomDateDeserializer extends StdDeserializer<Date> {
private static final long serialVersionUID = 1L;
private static SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
public CustomDateDeserializer() {
this(null);
}
public CustomDateDeserializer(Class<Date> t) {
super(t);
}
@Override
public Date deserialize(JsonParser parser, DeserializationContext context)
throws IOException, JsonProcessingException {
String date = parser.getText();
try {
return formatter.parse(date);
}
catch (ParseException e) {
e.printStackTrace();
}
return null;
}
}
Produzione
Thu Dec 20 00:00:00 IST 1984