com.alibaba.fastjson2.writer

Interface ObjectWriter<T>

Type Parameters:

T - the type of objects that this ObjectWriter can serialize

All Known Subinterfaces:

ObjectSerializer

All Known Implementing Classes:

ApacheLang3Support.PairWriter, CollectionCodec, Fastjson1xWriterModule.JSONAwareWriter, GeoJsonWriterModule.GeoJsonPointWriter, GeoJsonWriterModule.GeoJsonPolygonWriter, GeoJsonWriterModule.PointWriter, GuavaSupport.AsMapWriter, JavaBeanSerializer, JdbcSupport.ClobWriter, JdbcSupport.TimestampWriter, JdbcSupport.TimeWriter, JodaSupport.GregorianChronologyWriter, JodaSupport.ISOChronologyWriter, JodaSupport.LocalDateTimeWriter, JodaSupport.LocalDateWriter, JSONLibDataFormatSerializer, JSONSchema.JSONSchemaWriter, ListSerializer, ObjectWriter1, ObjectWriter10, ObjectWriter11, ObjectWriter12, ObjectWriter2, ObjectWriter3, ObjectWriter4, ObjectWriter5, ObjectWriter6, ObjectWriter7, ObjectWriter8, ObjectWriter9, ObjectWriterAdapter, ObjectWriterArray, ObjectWriterArrayFinal, ObjectWriterBaseModule.VoidObjectWriter, ObjectWriterBigInteger, ObjectWriterException, ObjectWriterImpDecimalArray, ObjectWriterImplAtomicBoolean, ObjectWriterImplAtomicInteger, ObjectWriterImplAtomicIntegerArray, ObjectWriterImplAtomicLong, ObjectWriterImplAtomicLongArray, ObjectWriterImplAtomicReference, ObjectWriterImplBigDecimal, ObjectWriterImplBitSet, ObjectWriterImplBoolean, ObjectWriterImplBoolValueArray, ObjectWriterImplBoolValueArrayLambda, ObjectWriterImplCalendar, ObjectWriterImplCharacter, ObjectWriterImplCharValueArray, ObjectWriterImplClass, ObjectWriterImplCollection, ObjectWriterImplCurrency, ObjectWriterImplDate, ObjectWriterImplDouble, ObjectWriterImplDoubleValueArray, ObjectWriterImplEnum, ObjectWriterImplFloat, ObjectWriterImplFloatValueArray, ObjectWriterImplInstant, ObjectWriterImplInt16, ObjectWriterImplInt16ValueArray, ObjectWriterImplInt32, ObjectWriterImplInt32Array, ObjectWriterImplInt32ValueArray, ObjectWriterImplInt64, ObjectWriterImplInt64Array, ObjectWriterImplInt64ValueArray, ObjectWriterImplInt8, ObjectWriterImplInt8Array, ObjectWriterImplInt8ValueArray, ObjectWriterImplJSONP, ObjectWriterImplList, ObjectWriterImplListEnum, ObjectWriterImplListStr, ObjectWriterImplLocalDate, ObjectWriterImplLocalDateTime, ObjectWriterImplLocale, ObjectWriterImplLocalTime, ObjectWriterImplMap, ObjectWriterImplMapEntry, ObjectWriterImplOffsetDateTime, ObjectWriterImplOffsetTime, ObjectWriterImplOptional, ObjectWriterImplOptionalDouble, ObjectWriterImplOptionalInt, ObjectWriterImplOptionalLong, ObjectWriterImplString, ObjectWriterImplStringArray, ObjectWriterImplTimeZone, ObjectWriterImplToString, ObjectWriterImplUUID, ObjectWriterImplXmlNode, ObjectWriterImplZonedDateTime, ObjectWriterMisc, ObjectWriterPrimitiveImpl, ObjectWriterRootName, SerializeConfig.ObjectSerializerAdapter, SimpleDateFormatSerializer, StringCodec, ToStringSerializer

public interface ObjectWriter<T>

ObjectWriter is responsible for serializing Java objects into JSON format. It provides a set of methods for writing objects to JSON, handling field mapping, and supporting various serialization features.

This interface supports various features including:

• Object serialization to JSON and JSONB formats
• Field mapping and value extraction
• Array mapping serialization
• Type information writing
• Custom feature configuration
• Filter support for property filtering

Example usage:

 // Get an ObjectWriter for a specific type
 ObjectWriter<User> writer = JSONFactory.getDefaultObjectWriterProvider().getObjectWriter(User.class);

 // Write to JSON string
 User user = new User(1, "John");
 String jsonString = writer.toJSONString(user);

 // Write to JSONWriter
 try (JSONWriter jsonWriter = JSONWriter.of()) {
     writer.write(jsonWriter, user);
     String result = jsonWriter.toString();
 }
 

Since:

2.0.0

Method Summary

Modifier and Type	Method and Description
default long	getFeatures() Gets the features enabled by this ObjectWriter.
default java.lang.Object	getFieldValue(java.lang.Object object, java.lang.String fieldName) Gets the value of a field from the specified object.
default FieldWriter	getFieldWriter(long hashCode) Gets the FieldWriter for the specified field hash code.
default FieldWriter	getFieldWriter(java.lang.String name) Gets the FieldWriter for the specified field name.
default java.util.List<FieldWriter>	getFieldWriters() Gets the list of FieldWriters associated with this ObjectWriter.
default boolean	hasFilter(JSONWriter jsonWriter) Checks if the JSONWriter has any filters enabled that would affect serialization.
default void	setFilter(Filter filter) Sets a filter for this ObjectWriter.
default void	setNameFilter(NameFilter nameFilter) Sets the name filter for this ObjectWriter.
default void	setPropertyFilter(PropertyFilter propertyFilter) Sets the property filter for this ObjectWriter.
default void	setPropertyPreFilter(PropertyPreFilter propertyPreFilter) Sets the property pre-filter for this ObjectWriter.
default void	setValueFilter(ValueFilter valueFilter) Sets the value filter for this ObjectWriter.
default java.lang.String	toJSONString(T object, JSONWriter.Feature... features) Converts an object to its JSON string representation using the specified features.
default void	write(JSONWriter jsonWriter, java.lang.Object object) Writes an object to the JSONWriter using default parameters.
void	write(JSONWriter jsonWriter, java.lang.Object object, java.lang.Object fieldName, java.lang.reflect.Type fieldType, long features) Writes an object to the JSONWriter with the given field name, field type, and features.
default void	writeArrayMapping(JSONWriter jsonWriter, java.lang.Object object, java.lang.Object fieldName, java.lang.reflect.Type fieldType, long features) Writes an object to the JSONWriter in array mapping format.
default void	writeArrayMappingJSONB(JSONWriter jsonWriter, java.lang.Object object) Writes an object to the JSONWriter in array mapping JSONB format.
default void	writeArrayMappingJSONB(JSONWriter jsonWriter, java.lang.Object object, java.lang.Object fieldName, java.lang.reflect.Type fieldType, long features) Writes an object to the JSONWriter in array mapping JSONB format with additional parameters.
default void	writeJSONB(JSONWriter jsonWriter, java.lang.Object object, java.lang.Object fieldName, java.lang.reflect.Type fieldType, long features) Writes an object to the JSONWriter in JSONB format.
default boolean	writeTypeInfo(JSONWriter jsonWriter) Writes type information to the JSON output.
default void	writeWithFilter(JSONWriter jsonWriter, java.lang.Object object) Writes an object to the JSONWriter with filter support using default parameters.
default void	writeWithFilter(JSONWriter jsonWriter, java.lang.Object object, java.lang.Object fieldName, java.lang.reflect.Type fieldType, long features) Writes an object to the JSONWriter with filter support.

Method Detail

getFeatures

default long getFeatures()

Gets the features enabled by this ObjectWriter.

Returns:

the enabled features as a bit mask

getFieldWriters

default java.util.List<FieldWriter> getFieldWriters()

Gets the list of FieldWriters associated with this ObjectWriter.

Returns:

the list of FieldWriters, or an empty list if none are available

getFieldWriter

default FieldWriter getFieldWriter(long hashCode)

Gets the FieldWriter for the specified field hash code.

Parameters:

hashCode - the hash code of the field name

Returns:

the FieldWriter for the field, or null if not found

getFieldValue

default java.lang.Object getFieldValue(java.lang.Object object,
                                       java.lang.String fieldName)

Gets the value of a field from the specified object.

Parameters:

object - the object from which to get the field value

fieldName - the name of the field to get

Returns:

the value of the field, or null if the field is not found

getFieldWriter

default FieldWriter getFieldWriter(java.lang.String name)

Gets the FieldWriter for the specified field name.

Parameters:

name - the name of the field

Returns:

the FieldWriter for the field, or null if not found

writeTypeInfo

default boolean writeTypeInfo(JSONWriter jsonWriter)

Writes type information to the JSON output. This is used for polymorphic serialization to include type information in the JSON output.

Parameters:

jsonWriter - the JSONWriter to which type information should be written

Returns:

true if type information was written, false otherwise

writeJSONB

default void writeJSONB(JSONWriter jsonWriter,
                        java.lang.Object object,
                        java.lang.Object fieldName,
                        java.lang.reflect.Type fieldType,
                        long features)

Writes an object to the JSONWriter in JSONB format.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

fieldName - the name of the field being written

fieldType - the type of the field being written

features - the features to use for writing

writeArrayMappingJSONB

default void writeArrayMappingJSONB(JSONWriter jsonWriter,
                                    java.lang.Object object)

Writes an object to the JSONWriter in array mapping JSONB format.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

writeArrayMappingJSONB

default void writeArrayMappingJSONB(JSONWriter jsonWriter,
                                    java.lang.Object object,
                                    java.lang.Object fieldName,
                                    java.lang.reflect.Type fieldType,
                                    long features)

Writes an object to the JSONWriter in array mapping JSONB format with additional parameters.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

fieldName - the name of the field being written

fieldType - the type of the field being written

features - the features to use for writing

writeArrayMapping

default void writeArrayMapping(JSONWriter jsonWriter,
                               java.lang.Object object,
                               java.lang.Object fieldName,
                               java.lang.reflect.Type fieldType,
                               long features)

Writes an object to the JSONWriter in array mapping format.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

fieldName - the name of the field being written

fieldType - the type of the field being written

features - the features to use for writing

hasFilter

default boolean hasFilter(JSONWriter jsonWriter)

Checks if the JSONWriter has any filters enabled that would affect serialization.

Parameters:

jsonWriter - the JSONWriter to check

Returns:

true if filters are enabled, false otherwise

write

default void write(JSONWriter jsonWriter,
                   java.lang.Object object)

Writes an object to the JSONWriter using default parameters.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

toJSONString

default java.lang.String toJSONString(T object,
                                      JSONWriter.Feature... features)

Converts an object to its JSON string representation using the specified features.

Parameters:

object - the object to convert to JSON

features - the JSON writer features to use

Returns:

the JSON string representation of the object

write

void write(JSONWriter jsonWriter,
           java.lang.Object object,
           java.lang.Object fieldName,
           java.lang.reflect.Type fieldType,
           long features)

Writes an object to the JSONWriter with the given field name, field type, and features.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

fieldName - the name of the field being written

fieldType - the type of the field being written

features - the features to use for writing

writeWithFilter

default void writeWithFilter(JSONWriter jsonWriter,
                             java.lang.Object object)

Writes an object to the JSONWriter with filter support using default parameters.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

writeWithFilter

default void writeWithFilter(JSONWriter jsonWriter,
                             java.lang.Object object,
                             java.lang.Object fieldName,
                             java.lang.reflect.Type fieldType,
                             long features)

Writes an object to the JSONWriter with filter support.

Parameters:

jsonWriter - the JSONWriter to which the object should be written

object - the object to write

fieldName - the name of the field being written

fieldType - the type of the field being written

features - the features to use for writing

Throws:

java.lang.UnsupportedOperationException - if the method is not implemented

setPropertyFilter

default void setPropertyFilter(PropertyFilter propertyFilter)

Sets the property filter for this ObjectWriter.

Parameters:

propertyFilter - the property filter to set

setValueFilter

default void setValueFilter(ValueFilter valueFilter)

Sets the value filter for this ObjectWriter.

Parameters:

valueFilter - the value filter to set

setNameFilter

default void setNameFilter(NameFilter nameFilter)

Sets the name filter for this ObjectWriter.

Parameters:

nameFilter - the name filter to set

setPropertyPreFilter

default void setPropertyPreFilter(PropertyPreFilter propertyPreFilter)

Sets the property pre-filter for this ObjectWriter.

Parameters:

propertyPreFilter - the property pre-filter to set

setFilter

default void setFilter(Filter filter)

Sets a filter for this ObjectWriter. The filter type is determined at runtime and the appropriate setter method is called.

Parameters:

filter - the filter to set