Convert object having date to/from json in java (jackson ObjectMapper)

Given the user defined object or POJO having date field, we would like to serialize the POJO to JSON.
During serialization, we would like save date as a timestamp or ISO format.
We will use the Jackson’s ObjectMapper to achieve the conversion.
We will create Person class and we will perform the following operations with Person class.
1. Convert Person Object to JSON
  - Serialize date as time stamp (default serialization)
2. Convert Person Object to JSON
  - Serialize date parameter as ISO format
3. Convert the JSON to person object
  - DeSerialize date as timestamp

Jackson ObjectMapper Maven Dependencies

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId> 
    <artifactId>jackson-databind</artifactId>
    <version>2.7.1</version> 
</dependency>

Program – Convert Date to/from timestamp in java (POJO <->JSON)

1.) Person Class:

The person class containing date data member.
We have overloaded toString method to display content of person object.

package org.learn;
 
import java.util.Date;
 
public class Person {
    public String firstName;
    public String lastName;
    public Date dob;
    public Person() {   
    }
    public Person(String firstName, String lastName,
                Date dob) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.dob = dob;
    }
    public String toString() {
        return "[" + firstName + " " + lastName +
               " " + dob.getTime() +"]";
    }
}

2.) JSONObjectConverter Class:

We are performing following operation in JSONObjectConverter class.

Convert Person Object to JSON
- Serialize date as time stamp (default serialization)
Convert Person Object to JSON
- Serialize date parameter as ISO format
Convert the JSON to person object
- DeSerialize date as timestamp

package org.learn;
 
import java.io.IOException;
import java.util.Date;
 
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
 
public class JSONObjectConverter 
{
    public static void main( String[] args ) throws IOException
    {
        ObjectMapper objectMapper = new ObjectMapper();
        //Set pretty printing of json
        objectMapper.enable(SerializationFeature.INDENT_OUTPUT);        
         
        Person objPerson = new Person("Mike", "harvey", new Date());
         
        //Convert Person object to json
        String json = objectMapper.writeValueAsString(objPerson);
        System.out.println("1. Convert Person to JSON - Date as timestamp");
        System.out.println(json);
         
        //Disable the timestamp serialization
        objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);  
         
        json = objectMapper.writeValueAsString(objPerson);
        System.out.println("2. Convert Person to JSON - Date without timestamp");
        System.out.println(json);
         
        //Convert to json to person object      
        System.out.println("3. Deserialize JSON to person object");
        Person objFromJson = objectMapper.readValue(json, Person.class);
        System.out.println(objFromJson); 
    }
}

Download Example Code-Jackson Object (Date) to JSON

Output – Date serialization & deserialization in java (POJO <-> JSON)

1. Convert Person to JSON - Date as timestamp
{
  "firstName" : "Mike",
  "lastName" : "harvey",
  "dob" : 1329142874258
}
2. Convert Person to JSON - Date without timestamp
{
  "firstName" : "Mike",
  "lastName" : "harvey",
  "dob" : "2012-02-13T14:21:14.258+0000"
}
3. Deserialize JSON to person object
[Mike harvey 1329142874258]

Jackson ObjectMapper Maven Dependencies

Program – Convert Date to/from timestamp in java (POJO <->JSON)

1.) Person Class:

2.) JSONObjectConverter Class:

Output – Date serialization & deserialization in java (POJO <-> JSON)

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