org.codehaus.jackson.map

## Class JsonSerializer<T>

- java.lang.Object
- - org.codehaus.jackson.map.JsonSerializer<T>

- Direct Known Subclasses:
    JsonSerializer.None, SerializerBase

      public abstract class JsonSerializer<T>
      extends Object

  Abstract class that defines API used by `ObjectMapper` (and other chained `JsonSerializer`s too) to serialize Objects of arbitrary types into JSON, using provided `JsonGenerator`.

  NOTE: it is recommended that custom serializers extend `SerializerBase` instead of this class, since it will implement many of optional methods of this class.

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Class and Description
    --- | ---
    `static class` | `JsonSerializer.None` This marker class is only to be used with annotations, to indicate that no serializer is configured.

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `JsonSerializer()`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `Class<T>` | `handledType()` Method for accessing type of Objects this serializer can handle.
    `boolean` | `isUnwrappingSerializer()` Accessor for checking whether this serializer is an "unwrapping" serializer; this is necessary to know since it may also require caller to suppress writing of the leading property name.
    `abstract void` | `serialize(T value, JsonGenerator jgen, SerializerProvider provider)` Method that can be called to ask implementation to serialize values of type this serializer handles.
    `void` | `serializeWithType(T value, JsonGenerator jgen, SerializerProvider provider, TypeSerializer typeSer)` Method that can be called to ask implementation to serialize values of type this serializer handles, using specified type serializer for embedding necessary type information.
    `JsonSerializer<T>` | `unwrappingSerializer()` Method that will return serializer instance that produces "unwrapped" serialization, if applicable for type being serialized (which is the case for some serializers that produce JSON Objects as output).

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### JsonSerializer

          public JsonSerializer()

  - ### Method Detail

    - #### unwrappingSerializer

          public JsonSerializer<T> unwrappingSerializer()

      Method that will return serializer instance that produces "unwrapped" serialization, if applicable for type being serialized (which is the case for some serializers that produce JSON Objects as output). If no unwrapped serializer can be constructed, will simply return serializer as-is.

      Default implementation just returns serializer as-is, indicating that no unwrapped variant exists

      Since:
        1.9

    - #### isUnwrappingSerializer

          public boolean isUnwrappingSerializer()

      Accessor for checking whether this serializer is an "unwrapping" serializer; this is necessary to know since it may also require caller to suppress writing of the leading property name.
      Since:
        1.9

    - #### serialize

          public abstract void serialize(T value,
                       JsonGenerator jgen,
                       SerializerProvider provider)
                                  throws IOException,
                                         JsonProcessingException

      Method that can be called to ask implementation to serialize values of type this serializer handles.
      Parameters:
        `value` - Value to serialize; can not be null.
        `jgen` - Generator used to output resulting Json content
        `provider` - Provider that can be used to get serializers for serializing Objects value contains, if any.
      Throws:
        `IOException`
        `JsonProcessingException`

    - #### serializeWithType

          public void serializeWithType(T value,
                               JsonGenerator jgen,
                               SerializerProvider provider,
                               TypeSerializer typeSer)
                                 throws IOException,
                                        JsonProcessingException

      Method that can be called to ask implementation to serialize values of type this serializer handles, using specified type serializer for embedding necessary type information.

      Default implementation will ignore serialization of type information, and just calls `serialize(T, org.codehaus.jackson.JsonGenerator, org.codehaus.jackson.map.SerializerProvider)`: serializers that can embed type information should override this to implement actual handling. Most common such handling is done by something like:

            // note: method to call depends on whether this type is serialized as JSON scalar, object or Array!
            typeSer.writeTypePrefixForScalar(value, jgen);
            serialize(value, jgen, provider);
            typeSer.writeTypeSuffixForScalar(value, jgen);

      Parameters:
        `value` - Value to serialize; can not be null.
        `jgen` - Generator used to output resulting Json content
        `provider` - Provider that can be used to get serializers for serializing Objects value contains, if any.
        `typeSer` - Type serializer to use for including type information
      Throws:
        `IOException`
        `JsonProcessingException`
      Since:
        1.5

    - #### handledType

          public Class<T> handledType()

      Method for accessing type of Objects this serializer can handle. Note that this information is not guaranteed to be exact -- it may be a more generic (super-type) -- but it should not be incorrect (return a non-related type).

      Default implementation will return null, which essentially means same as returning `Object.class` would; that is, that nothing is known about handled type.