Package org.bson.codecs

Class MapCodec

java.lang.Object

org.bson.codecs.MapCodec

All Implemented Interfaces:

Codec<Map<String,Object>>, Decoder<Map<String,Object>>, Encoder<Map<String,Object>>

public class MapCodec
extends Object
implements Codec<Map<String,Object>>

A Codec for Map instances.

Since:

3.5

Constructor Summary

Constructors

Constructor	Description
MapCodec()	Construct a new instance with a default CodecRegistry
MapCodec(CodecRegistry registry)	Construct a new instance with the given registry
MapCodec(CodecRegistry registry, BsonTypeClassMap bsonTypeClassMap)	Construct a new instance with the given registry and BSON type class map.
MapCodec(CodecRegistry registry, BsonTypeClassMap bsonTypeClassMap, Transformer valueTransformer)	Construct a new instance with the given registry and BSON type class map.

Method Summary

Modifier and Type	Method	Description
Map<String,Object>	decode(BsonReader reader, DecoderContext decoderContext)	Decodes a BSON value from the given reader into an instance of the type parameter T.
void	encode(BsonWriter writer, Map<String,Object> map, EncoderContext encoderContext)	Encode an instance of the type parameter T into a BSON value.
Class<Map<String,Object>>	getEncoderClass()	Returns the Class instance that this encodes.

Methods inherited from class java.lang.Object

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

Constructor Detail

MapCodec

public MapCodec()

Construct a new instance with a default CodecRegistry

MapCodec

public MapCodec(CodecRegistry registry)

Construct a new instance with the given registry

Parameters:

registry - the registry

MapCodec

public MapCodec(CodecRegistry registry,
                BsonTypeClassMap bsonTypeClassMap)

Construct a new instance with the given registry and BSON type class map.

Parameters:

registry - the registry

bsonTypeClassMap - the BSON type class map

MapCodec

public MapCodec(CodecRegistry registry,
                BsonTypeClassMap bsonTypeClassMap,
                Transformer valueTransformer)

Construct a new instance with the given registry and BSON type class map. The transformer is applied as a last step when decoding values, which allows users of this codec to control the decoding process. For example, a user of this class could substitute a value decoded as a Document with an instance of a special purpose class (e.g., one representing a DBRef in MongoDB).

Parameters:

registry - the registry

bsonTypeClassMap - the BSON type class map

valueTransformer - the value transformer to use as a final step when decoding the value of any field in the map

Method Detail

encode

public void encode(BsonWriter writer,
                   Map<String,Object> map,
                   EncoderContext encoderContext)

Description copied from interface: Encoder

Encode an instance of the type parameter T into a BSON value.

Specified by:

encode in interface Encoder<Map<String,Object>>

Parameters:

writer - the BSON writer to encode into

map - the value to encode

encoderContext - the encoder context

decode

public Map<String,Object> decode(BsonReader reader,
                                 DecoderContext decoderContext)

Description copied from interface: Decoder

Decodes a BSON value from the given reader into an instance of the type parameter T.

Specified by:

decode in interface Decoder<Map<String,Object>>

Parameters:

reader - the BSON reader

decoderContext - the decoder context

Returns:

an instance of the type parameter T.

getEncoderClass

public Class<Map<String,Object>> getEncoderClass()

Description copied from interface: Encoder

Returns the Class instance that this encodes. This is necessary because Java does not reify generic types.

Specified by:

getEncoderClass in interface Encoder<Map<String,Object>>

Returns:

the Class instance that this encodes.