How to format LocalDate object using Jackson?

We have a Recording class which has a Java 8 java.time.LocalDate property. We need to deserialize and serialize this property from and to JSON string. To do this we can use the @JsonDeserialize and @JsonSerialize annotations to annotate the LocalDate property of the Recording class.

@JsonDeserialize(using = LocalDateDeserializer.class)
@JsonSerialize(using = LocalDateSerializer.class)
private LocalDate releaseDate;

To use the annotation we need to create a class to deserialize and serialize the value. To create a deserializer class we create a class that extends StdDeserializer. The serializer class extends the StdSerializer class. Below is the definition of the LocalDateSerializer and LocalDateDeserializer class.

package org.kodejava.example.jackson;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.ser.std.StdSerializer;

import java.io.IOException;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;

public class LocalDateSerializer extends StdSerializer<LocalDate> {

    public LocalDateSerializer() {
        super(LocalDate.class);
    }

    @Override
    public void serialize(LocalDate value, JsonGenerator generator, SerializerProvider provider) throws IOException {
        generator.writeString(value.format(DateTimeFormatter.ISO_LOCAL_DATE));
    }
}
package org.kodejava.example.jackson;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;

import java.io.IOException;
import java.time.LocalDate;

public class LocalDateDeserializer extends StdDeserializer<LocalDate> {

    protected LocalDateDeserializer() {
        super(LocalDate.class);
    }

    @Override
    public LocalDate deserialize(JsonParser parser, DeserializationContext context) throws IOException {
        return LocalDate.parse(parser.readValueAs(String.class));
    }
}

And here is the complete definition of the Recording class.

package org.kodejava.example.jackson;

import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;

import java.time.LocalDate;
import java.util.Objects;

public class Recording {
    private Long id;
    private String title;

    @JsonDeserialize(using = LocalDateDeserializer.class)
    @JsonSerialize(using = LocalDateSerializer.class)
    private LocalDate releaseDate;

    private Artist artist;
    private Label label;

    public Recording() {
    }

    public Recording(Long id, String title, LocalDate releaseDate) {
        this.id = id;
        this.title = title;
        this.releaseDate = releaseDate;
    }

    // Getters and Setters
}

Maven Dependencies

<!-- http://repo1.maven.org/maven2/com/fasterxml/jackson/core/jackson-databind/2.8.6/jackson-databind-2.8.6.jar -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.8.6</version>
</dependency>

How to convert java.time.LocalDate to java.util.Date?

The following code snippet demonstrate how to convert java.time.LocalDate to java.util.Date and vice versa. In the first part of the code snippet we convert LocalDate to Date and back to LocalDate object. On the second part we convert LocalDateTime to Date and back to LocalDateTime object.

package org.kodejava.example.datetime;

import java.time.*;
import java.util.Date;

public class LocalDateToDate {
    public static void main(String[] args) {
        // Convert java.time.LocalDate to java.util.Date and back to
        // java.time.LocalDate
        LocalDate localDate = LocalDate.now();
        System.out.println("LocalDate = " + localDate);

        Date date1 = Date.from(localDate.atStartOfDay(ZoneId.systemDefault()).toInstant());
        System.out.println("Date      = " + date1);

        localDate = date1.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
        System.out.println("LocalDate = " + localDate);
        System.out.println();

        // Convert java.time.LocalDateTime to java.util.Date and back to
        // java.time.LocalDateTime
        LocalDateTime localDateTime = LocalDateTime.now();
        System.out.println("LocalDateTime = " + localDateTime);

        Date date2 = Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant());
        System.out.println("Date          = " + date2);

        localDateTime = date2.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime();
        System.out.println("LocalDateTime = " + localDateTime);
    }
}

The result of the code snippet:

LocalDate = 2017-02-14
Date      = Tue Feb 14 00:00:00 WITA 2017
LocalDate = 2017-02-14

LocalDateTime = 2017-02-14T10:34:49.562
Date          = Tue Feb 14 10:34:49 WITA 2017
LocalDateTime = 2017-02-14T10:34:49.562