Package org.apache.qpid.protonj2.codec.decoders.primitives

Class AbstractMapTypeDecoder

java.lang.Object

org.apache.qpid.protonj2.codec.decoders.AbstractPrimitiveTypeDecoder<Map>

org.apache.qpid.protonj2.codec.decoders.primitives.AbstractMapTypeDecoder

All Implemented Interfaces:

MapTypeDecoder, PrimitiveTypeDecoder<Map>, StreamTypeDecoder<Map>, TypeDecoder<Map>

Direct Known Subclasses:

Map32TypeDecoder, Map8TypeDecoder

public abstract class AbstractMapTypeDecoder
extends AbstractPrimitiveTypeDecoder<Map>
implements MapTypeDecoder

Base for the various Map type decoders used to read AMQP Map values.

Constructor Summary

Constructors

Constructor	Description
AbstractMapTypeDecoder()

Method Summary

Modifier and Type	Method	Description
Map<Object,Object>	readValue(InputStream stream, StreamDecoderState state)	Reads the next type from the given buffer and returns it.
Map<Object,Object>	readValue(ProtonBuffer buffer, DecoderState state)	Reads the next type from the given buffer and returns it.
<KeyType> void	scanKeys(InputStream stream, StreamDecoderState state, StreamScanningContext<KeyType> context, BiConsumer<KeyType,Object> matchConsumer)	Scan the encoded Map keys matching on predetermined key value encodings to quickly find mappings that are of interest and then only decoding the value portion of the matched key / value pair.
<KeyType> void	scanKeys(ProtonBuffer buffer, DecoderState state, ScanningContext<KeyType> context, BiConsumer<KeyType,Object> matchConsumer)	Scan the encoded Map keys matching on predetermined key value encodings to quickly find mappings that are of interest and then only decoding the value portion of the matched key / value pair.
void	skipValue(InputStream stream, StreamDecoderState state)	Skips over the bytes that compose the type this descriptor decodes.
void	skipValue(ProtonBuffer buffer, DecoderState state)	Skips over the bytes that compose the type this descriptor decodes.

Methods inherited from class org.apache.qpid.protonj2.codec.decoders.AbstractPrimitiveTypeDecoder

isArrayType, isJavaPrimitive, isNull, readArrayElements, readArrayElements

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.qpid.protonj2.codec.decoders.primitives.MapTypeDecoder

getTypeClass, readCount, readCount

Methods inherited from interface org.apache.qpid.protonj2.codec.decoders.PrimitiveTypeDecoder

getTypeCode, isJavaPrimitive, isPrimitive

Methods inherited from interface org.apache.qpid.protonj2.codec.StreamTypeDecoder

getTypeClass, isArrayType, isNull, readArrayElements, readSize

Methods inherited from interface org.apache.qpid.protonj2.codec.TypeDecoder

isArrayType, isNull, readArrayElements, readSize

Constructor Details

AbstractMapTypeDecoder

public AbstractMapTypeDecoder()

Method Details

readValue

public Map<Object,Object> readValue(ProtonBuffer buffer,
 DecoderState state)
                             throws DecodeException

Description copied from interface: TypeDecoder

Reads the next type from the given buffer and returns it.

Specified by:

readValue in interface TypeDecoder<Map>

Parameters:

buffer - the source of encoded data.

state - the current state of the decoder.

Returns:

the next instance in the stream that this decoder handles.

Throws:

DecodeException - if an error is encountered while reading the next value.

skipValue

public void skipValue(ProtonBuffer buffer,
 DecoderState state)
               throws DecodeException

Description copied from interface: TypeDecoder

Skips over the bytes that compose the type this descriptor decodes.

Skipping values can be used when the type is not used or processed by the application doing the decoding. An example might be an AMQP message decoder that only needs to decode certain parts of the message and not others.

Specified by:

skipValue in interface TypeDecoder<Map>

Parameters:

buffer - The buffer that contains the encoded type.

state - The decoder state.

Throws:

DecodeException - if an error occurs while skipping the value.

scanKeys

public <KeyType> void scanKeys(ProtonBuffer buffer,
 DecoderState state,
 ScanningContext<KeyType> context,
 BiConsumer<KeyType,Object> matchConsumer)
                        throws DecodeException

Description copied from interface: MapTypeDecoder

Scan the encoded Map keys matching on predetermined key value encodings to quickly find mappings that are of interest and then only decoding the value portion of the matched key / value pair. This allows for quick checks of incoming Map types without the performance penalty of a full decode. After the method returns the contexts of the encoded Map in the provided buffer will have been consumed and the next type can be decoded.

Each matching key / value mapping triggers a call to the provided BiConsumer with the key that triggered the match (generally a cached non-decoded value) and the decoded value mapped to that key. The caller should use the consumer to trigger actions based on the matches found in the mappings which avoid full decodings of large maps when only a limited set of values is desired.

Specified by:

scanKeys in interface MapTypeDecoder

Type Parameters:

KeyType - The key type is used when calling the match consumer

Parameters:

buffer - The buffer containing the encoded Map type.

state - The DecoderState used during this decode.

context - The previously created and configured ScanningContext

matchConsumer - The consumer that will be notified when a matching key is found.

Throws:

DecodeException - if an error occurs reading the value

readValue

public Map<Object,Object> readValue(InputStream stream,
 StreamDecoderState state)
                             throws DecodeException

Description copied from interface: StreamTypeDecoder

Reads the next type from the given buffer and returns it.

Specified by:

readValue in interface StreamTypeDecoder<Map>

Parameters:

stream - the source of encoded data.

state - the current state of the decoder.

Returns:

the next instance in the stream that this decoder handles.

Throws:

DecodeException - if an error is encountered while reading the next value.

skipValue

public void skipValue(InputStream stream,
 StreamDecoderState state)
               throws DecodeException

Description copied from interface: StreamTypeDecoder

Skips over the bytes that compose the type this descriptor decodes.

Skipping values can be used when the type is not used or processed by the application doing the decoding. An example might be an AMQP message decoder that only needs to decode certain parts of the message and not others.

Specified by:

skipValue in interface StreamTypeDecoder<Map>

Parameters:

stream - The stream that contains the encoded type.

state - The decoder state.

Throws:

DecodeException - if an error occurs while skipping the value.

scanKeys

public <KeyType> void scanKeys(InputStream stream,
 StreamDecoderState state,
 StreamScanningContext<KeyType> context,
 BiConsumer<KeyType,Object> matchConsumer)
                        throws DecodeException

Description copied from interface: MapTypeDecoder

Scan the encoded Map keys matching on predetermined key value encodings to quickly find mappings that are of interest and then only decoding the value portion of the matched key / value pair. This allows for quick checks of incoming Map types without the performance penalty of a full decode. After the method returns the contexts of the encoded Map in the provided stream will have been consumed and the next type can be decoded.

Each matching key / value mapping triggers a call to the provided BiConsumer with the key that triggered the match (generally a cached non-decoded value) and the decoded value mapped to that key. The caller should use the consumer to trigger actions based on the matches found in the mappings which avoid full decodings of large maps when only a limited set of values is desired.

Specified by:

scanKeys in interface MapTypeDecoder

Type Parameters:

KeyType - The key type is used when calling the match consumer

Parameters:

stream - The InputStream containing the encoded Map type.

state - The StreamDecoderState used during this decode.

context - The previously created and configured ScanningContext

matchConsumer - The consumer that will be notified when a matching key is found.

Throws:

DecodeException - if an error occurs reading the value