com.fasterxml.jackson.databind.JsonSerializable Maven / Gradle / Ivy
package com.fasterxml.jackson.databind;
import java.io.IOException;
import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
/**
* Interface that can be implemented by objects that know how to
* serialize themselves to JSON, using {@link JsonGenerator}
* (and {@link SerializerProvider} if necessary).
*
* Note that implementing this interface binds implementing object
* closely to Jackson API, and that it is often not necessary to do
* so -- if class is a bean, it can be serialized without
* implementing this interface.
*
* Note that while it is possible to just directly implement {@link JsonSerializable},
* actual implementations are strongly recommended to instead extend
* {@link JsonSerializable.Base}.
*/
public interface JsonSerializable
{
/**
* Serialization method called when no additional type information is
* to be included in serialization.
*/
public void serialize(JsonGenerator gen, SerializerProvider serializers) throws IOException;
/**
* Serialization method called when additional type information is
* expected to be included in serialization, for deserialization to use.
*
* Usually implementation consists of a call to one of methods
* in {@link TypeSerializer} (such as {@link TypeSerializer#writeTypePrefixForObject(Object, JsonGenerator)})
* followed by serialization of contents,
* followed by another call to {@link TypeSerializer}
* (such as {@link TypeSerializer#writeTypeSuffixForObject(Object, JsonGenerator)}).
* Exact methods to call in {@link TypeSerializer} depend on shape of JSON Object used
* (Array, Object or scalar like String/Number/Boolean).
*
* Note that some types (most notably, "natural" types: String, Integer,
* Double and Boolean) never include type information.
*/
public void serializeWithType(JsonGenerator gen, SerializerProvider serializers,
TypeSerializer typeSer) throws IOException;
/**
* Base class with minimal implementation, as well as couple of extension methods
* that core Jackson databinding makes use of.
* Use of this base class is strongly recommended over directly implementing
* {@link JsonSerializable}.
*
* @since 2.6
*/
public abstract static class Base implements JsonSerializable
{
/**
* Method that may be called on instance to determine if it is considered
* "empty" for purposes of serialization filtering or not.
*/
public boolean isEmpty(SerializerProvider serializers) {
return false;
}
}
}