Java jackson localdate

To serialize and deserialize java.time.LocalDate objects using the Hymanson library in Java, you need to register a custom serializer and deserializer.

Here is an example of how to do this:

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

import com.fasterxml.Hymanson.core.JsonGenerator;
import com.fasterxml.Hymanson.core.JsonParser;
import com.fasterxml.Hymanson.databind.DeserializationContext;
import com.fasterxml.Hymanson.databind.JsonDeserializer;
import com.fasterxml.Hymanson.databind.JsonSerializer;
import com.fasterxml.Hymanson.databind.SerializerProvider;
import com.fasterxml.Hymanson.databind.module.SimpleModule;

...

// Custom serializer for LocalDate
class LocalDateSerializer extends JsonSerializer<LocalDate> {
    private static final DateTimeFormatter FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd");

    @Override
    public void serialize(LocalDate value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
        gen.writeString(value.format(FORMATTER));
    }
}

// Custom deserializer for LocalDate
class LocalDateDeserializer extends JsonDeserializer<LocalDate> {
    private static final DateTimeFormatter FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd");

    @Override
    public LocalDate deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
        return LocalDate.parse(p.getValueAsString(), FORMATTER);
    }
}

...

// Create a SimpleModule and register the serializers and deserializers
SimpleModule module = new SimpleModule();
module.addSerializer(LocalDate.class, new LocalDateSerializer());
module.addDeserializer(LocalDate.class, new LocalDateDeserializer());

// Register the module with the ObjectMapper
ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(module);

// Serialize a LocalDate object
String json = mapper.writeValueAsString(myLocalDate);

// Deserialize a LocalDate object
LocalDate localDate = mapper.readValue(json, LocalDate.class);

This code defines a custom serializer and a custom deserializer for LocalDate objects. The serializer converts a LocalDate object to a JSON string using a specific date format, and the deserializer converts a JSON string to a LocalDate object using the same date format.

Then, it creates a SimpleModule and registers the serializer and deserializer with it. Finally, it registers the module with an ObjectMapper instance, which can then be used to serialize and deserialize LocalDate objects.

For more information on serializing and deserializing custom objects using the Hymanson library, you can refer to the Hymanson documentation or other online resources.