com.fasterxml.jackson.databind.ser.std

Class StdDelegatingSerializer

java.lang.Object

com.fasterxml.jackson.databind.JsonSerializer<T>

com.fasterxml.jackson.databind.ser.std.StdSerializer<Object>

com.fasterxml.jackson.databind.ser.std.StdDelegatingSerializer

All Implemented Interfaces:

JsonFormatVisitable, SchemaAware, ContextualSerializer, ResolvableSerializer, Serializable

public class StdDelegatingSerializer
extends StdSerializer<Object>
implements ContextualSerializer, ResolvableSerializer, JsonFormatVisitable, SchemaAware

Serializer implementation where given Java type is first converted to an intermediate "delegate type" (using a configured Converter, and then this delegate value is serialized by Jackson.

Note that although types may be related, they must not be same; trying to do this will result in an exception.

Since:

2.1

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class com.fasterxml.jackson.databind.JsonSerializer

JsonSerializer.None

Field Summary

Fields

Modifier and Type	Field and Description
protected Converter<Object,?>	_converter
protected JsonSerializer<Object>	_delegateSerializer Underlying serializer for type T.
protected JavaType	_delegateType Fully resolved delegate type, with generic information if any available.

Fields inherited from class com.fasterxml.jackson.databind.ser.std.StdSerializer

_handledType

Constructor Summary

Constructors

Constructor and Description
StdDelegatingSerializer(Class<T> cls, Converter<T,?> converter)
StdDelegatingSerializer(Converter<?,?> converter)
StdDelegatingSerializer(Converter<Object,?> converter, JavaType delegateType, JsonSerializer<?> delegateSerializer)

Method Summary

Modifier and Type	Method and Description
protected JsonSerializer<Object>	_findSerializer(Object value, SerializerProvider serializers) Helper method used for locating serializer to use in dynamic use case, where actual type value gets converted to is not specified beyond basic Object, and where serializer needs to be located dynamically based on actual value type.
void	acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint) Default implementation specifies no format.
protected Object	convertValue(Object value) Method called to convert from source Java value into delegate value (which will be serialized using standard Jackson serializer for delegate type)
JsonSerializer<?>	createContextual(SerializerProvider provider, BeanProperty property) Method called to see if a different (or differently configured) serializer is needed to serialize values of specified property.
protected Converter<Object,?>	getConverter()
JsonSerializer<?>	getDelegatee() Accessor that can be used to determine if this serializer uses another serializer for actual serialization, by delegating calls.
JsonNode	getSchema(SerializerProvider provider, Type typeHint) Default implementation simply claims type is "string"; usually overriden by custom serializers.
JsonNode	getSchema(SerializerProvider provider, Type typeHint, boolean isOptional) Default implementation simply claims type is "string"; usually overriden by custom serializers.
boolean	isEmpty(Object value) Deprecated.
boolean	isEmpty(SerializerProvider prov, Object value) Method called to check whether given serializable value is considered "empty" value (for purposes of suppressing serialization of empty values).
void	resolve(SerializerProvider provider) Method called after SerializerProvider has registered the serializer, but before it has returned it to the caller.
void	serialize(Object value, com.fasterxml.jackson.core.JsonGenerator gen, SerializerProvider provider) Method that can be called to ask implementation to serialize values of type this serializer handles.
void	serializeWithType(Object value, com.fasterxml.jackson.core.JsonGenerator gen, 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.
protected StdDelegatingSerializer	withDelegate(Converter<Object,?> converter, JavaType delegateType, JsonSerializer<?> delegateSerializer) Method used for creating resolved contextual instances.

Methods inherited from class com.fasterxml.jackson.databind.ser.std.StdSerializer

createObjectNode, createSchemaNode, createSchemaNode, findConvertingContentSerializer, findPropertyFilter, handledType, isDefaultSerializer, wrapAndThrow, wrapAndThrow

Methods inherited from class com.fasterxml.jackson.databind.JsonSerializer

isUnwrappingSerializer, properties, replaceDelegatee, unwrappingSerializer, usesObjectId, withFilterId

Methods inherited from class java.lang.Object

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

Field Detail

_converter

protected final Converter<Object,?> _converter

_delegateType

protected final JavaType _delegateType

Fully resolved delegate type, with generic information if any available.

_delegateSerializer

protected final JsonSerializer<Object> _delegateSerializer

Underlying serializer for type T.

Constructor Detail

StdDelegatingSerializer

public StdDelegatingSerializer(Converter<?,?> converter)

StdDelegatingSerializer

public StdDelegatingSerializer(Class<T> cls,
                               Converter<T,?> converter)

StdDelegatingSerializer

public StdDelegatingSerializer(Converter<Object,?> converter,
                               JavaType delegateType,
                               JsonSerializer<?> delegateSerializer)

Method Detail

withDelegate

protected StdDelegatingSerializer withDelegate(Converter<Object,?> converter,
                                               JavaType delegateType,
                                               JsonSerializer<?> delegateSerializer)

Method used for creating resolved contextual instances. Must be overridden when sub-classing.

resolve

public void resolve(SerializerProvider provider)
             throws JsonMappingException

Description copied from interface: ResolvableSerializer

Method called after SerializerProvider has registered the serializer, but before it has returned it to the caller. Called object can then resolve its dependencies to other types, including self-references (direct or indirect).

Note that this method does NOT return serializer, since resolution is not allowed to change actual serializer to use.

Specified by:

resolve in interface ResolvableSerializer

Parameters:

provider - Provider that has constructed serializer this method is called on.

Throws:

JsonMappingException

createContextual

public JsonSerializer<?> createContextual(SerializerProvider provider,
                                          BeanProperty property)
                                   throws JsonMappingException

Description copied from interface: ContextualSerializer

Method called to see if a different (or differently configured) serializer is needed to serialize values of specified property. Note that instance that this method is called on is typically shared one and as a result method should NOT modify this instance but rather construct and return a new instance. This instance should only be returned as-is, in case it is already suitable for use.

Specified by:

createContextual in interface ContextualSerializer

Parameters:

provider - Serializer provider to use for accessing config, other serializers

property - Method or field that represents the property (and is used to access value to serialize). Should be available; but there may be cases where caller can not provide it and null is passed instead (in which case impls usually pass 'this' serializer as is)

Returns:

Serializer to use for serializing values of specified property; may be this instance or a new instance.

Throws:

JsonMappingException

getConverter

protected Converter<Object,?> getConverter()

getDelegatee

public JsonSerializer<?> getDelegatee()

Description copied from class: JsonSerializer

Accessor that can be used to determine if this serializer uses another serializer for actual serialization, by delegating calls. If so, will return immediate delegate (which itself may delegate to further serializers); otherwise will return null.

Overrides:

getDelegatee in class JsonSerializer<Object>

Returns:

Serializer this serializer delegates calls to, if null; null otherwise.

serialize

public void serialize(Object value,
                      com.fasterxml.jackson.core.JsonGenerator gen,
                      SerializerProvider provider)
               throws IOException

Description copied from class: JsonSerializer

Method that can be called to ask implementation to serialize values of type this serializer handles.

Specified by:

serialize in class StdSerializer<Object>

Parameters:

value - Value to serialize; can not be null.

gen - 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

serializeWithType

public void serializeWithType(Object value,
                              com.fasterxml.jackson.core.JsonGenerator gen,
                              SerializerProvider provider,
                              TypeSerializer typeSer)
                       throws IOException

Description copied from class: JsonSerializer

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 throw UnsupportedOperationException to indicate that proper type handling needs to be implemented.

For simple datatypes written as a single scalar value (JSON String, Number, Boolean), implementation would look like:

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

and implementations for type serialized as JSON Arrays or Objects would differ slightly, as START-ARRAY>/END-ARRAY and START-OBJECT>/END-OBJECT pairs need to be properly handled with respect to serializing of contents.

Overrides:

serializeWithType in class JsonSerializer<Object>

Parameters:

value - Value to serialize; can not be null.

gen - 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

isEmpty

@Deprecated
public boolean isEmpty(Object value)

Deprecated.

Description copied from class: JsonSerializer

Method called to check whether given serializable value is considered "empty" value (for purposes of suppressing serialization of empty values).

Default implementation will consider only null values to be empty.

Overrides:

isEmpty in class JsonSerializer<Object>

isEmpty

public boolean isEmpty(SerializerProvider prov,
                       Object value)

Description copied from class: JsonSerializer

Method called to check whether given serializable value is considered "empty" value (for purposes of suppressing serialization of empty values).

Default implementation will consider only null values to be empty.

NOTE: replaces JsonSerializer.isEmpty(Object), deprecated in 2.5

Overrides:

isEmpty in class JsonSerializer<Object>

getSchema

public JsonNode getSchema(SerializerProvider provider,
                          Type typeHint)
                   throws JsonMappingException

Description copied from class: StdSerializer

Default implementation simply claims type is "string"; usually overriden by custom serializers.

Specified by:

getSchema in interface SchemaAware

Overrides:

getSchema in class StdSerializer<Object>

Parameters:

provider - The serializer provider.

typeHint - A hint about the type.

Returns:

Json-schema for this serializer.

Throws:

JsonMappingException

getSchema

public JsonNode getSchema(SerializerProvider provider,
                          Type typeHint,
                          boolean isOptional)
                   throws JsonMappingException

Description copied from class: StdSerializer

Default implementation simply claims type is "string"; usually overriden by custom serializers.

Specified by:

getSchema in interface SchemaAware

Overrides:

getSchema in class StdSerializer<Object>

Parameters:

provider - The serializer provider.

typeHint - A hint about the type.

isOptional - Is the type optional

Returns:

Json-schema for this serializer.

Throws:

JsonMappingException

acceptJsonFormatVisitor

public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor,
                                    JavaType typeHint)
                             throws JsonMappingException

Description copied from class: StdSerializer

Default implementation specifies no format. This behavior is usually overriden by custom serializers.

Specified by:

acceptJsonFormatVisitor in interface JsonFormatVisitable

Overrides:

acceptJsonFormatVisitor in class StdSerializer<Object>

typeHint - Type of element (entity like property) being visited

Throws:

JsonMappingException

convertValue

protected Object convertValue(Object value)

Method called to convert from source Java value into delegate value (which will be serialized using standard Jackson serializer for delegate type)

The default implementation uses configured Converter to do conversion.

Parameters:

value - Value to convert

Returns:

Result of conversion

_findSerializer

protected JsonSerializer<Object> _findSerializer(Object value,
                                                 SerializerProvider serializers)
                                          throws JsonMappingException

Helper method used for locating serializer to use in dynamic use case, where actual type value gets converted to is not specified beyond basic Object, and where serializer needs to be located dynamically based on actual value type.

Throws:

JsonMappingException

Since:

2.6