Spring Framework 6.1.4 · org.springframework.messaging.simp.stomp.BufferingStompDecoder

An extension of org.springframework.messaging.simp.stomp.StompDecoder that buffers content remaining in the input ByteBuffer after the parent class has read all (complete) STOMP frames from it. The remaining content represents an incomplete STOMP frame. When called repeatedly with additional data, the decode method returns one or more messages or, if there is not enough data still, continues to buffer.

A single instance of this decoder can be invoked repeatedly to read all messages from a single stream (e.g. WebSocket session) as long as decoding does not fail. If there is an exception, StompDecoder instance should not be used any more as its internal state is not guaranteed to be consistent. It is expected that the underlying session is closed at that point.

Field Summary

Modifier and Type	Field and Description
private final int	bufferSizeLimit
private final Queue<ByteBuffer>	chunks
private volatile Integer	expectedContentLength
private final StompDecoder	stompDecoder

Constructor Summary

Access	Constructor and Description
public	BufferingStompDecoder(StompDecoder the target decoder to wrap stompDecoder, int the buffer size limit bufferSizeLimit) Create a new `BufferingStompDecoder` wrapping the given `StompDecoder`.

Method Summary

Modifier and Type	Method and Description
private ByteBuffer	assembleChunksAndReset()
private void	checkBufferLimits()
public List<Message<byte[]>>	Returns: decoded messages or an empty list decode(ByteBuffer a buffer containing new data to decode newBuffer) Decodes one or more STOMP frames from the given `ByteBuffer` into a list of `Messages`.
public int	getBufferSize() Calculate the current buffer size.
public final int	getBufferSizeLimit() Return the configured buffer size limit.
public Integer	getExpectedContentLength() Get the expected content length of the currently buffered, incomplete STOMP frame.
public final StompDecoder	getStompDecoder() Return the wrapped `StompDecoder`.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

bufferSizeLimit	back to summary
private final int bufferSizeLimit

chunks	back to summary
private final Queue<ByteBuffer> chunks

expectedContentLength	back to summary
private volatile Integer expectedContentLength Annotations @Nullable

stompDecoder	back to summary
private final StompDecoder stompDecoder

Constructor Detail

BufferingStompDecoder back to summary

BufferingStompDecoder	back to summary
public BufferingStompDecoder(StompDecoder stompDecoder, int bufferSizeLimit) Create a new `BufferingStompDecoder` wrapping the given `StompDecoder`. Parameters stompDecoder:StompDecoder the target decoder to wrap bufferSizeLimit:int the buffer size limit

public BufferingStompDecoder(StompDecoder stompDecoder, int bufferSizeLimit)

Create a new BufferingStompDecoder wrapping the given StompDecoder.

Parameters

stompDecoder:StompDecoder: the target decoder to wrap
bufferSizeLimit:int: the buffer size limit

Method Detail

assembleChunksAndReset	back to summary
private ByteBuffer assembleChunksAndReset()

checkBufferLimits	back to summary
private void checkBufferLimits()

decode back to summary

decode	back to summary
public List<Message<byte[]>> decode(ByteBuffer newBuffer) Decodes one or more STOMP frames from the given `ByteBuffer` into a list of `Messages`. If there was enough data to parse a "content-length" header, then the value is used to determine how much more data is needed before a new attempt to decode is made. If there was not enough data to parse the "content-length", or if there is "content-length" header, every subsequent call to decode attempts to parse again with all available data. Therefore the presence of a "content-length" header helps to optimize the decoding of large messages. Parameters newBuffer:ByteBuffer a buffer containing new data to decode Returns:List<Message<byte[]>> decoded messages or an empty list Exceptions StompConversionException: raised in case of decoding issues

public List<Message<byte[]>> decode(ByteBuffer newBuffer)

Decodes one or more STOMP frames from the given ByteBuffer into a list of Messages.

If there was enough data to parse a "content-length" header, then the value is used to determine how much more data is needed before a new attempt to decode is made.

If there was not enough data to parse the "content-length", or if there is "content-length" header, every subsequent call to decode attempts to parse again with all available data. Therefore the presence of a "content-length" header helps to optimize the decoding of large messages.

Parameters

newBuffer:ByteBuffer: a buffer containing new data to decode

Returns:List<Message<byte[]>>

decoded messages or an empty list

Exceptions

StompConversionException:: raised in case of decoding issues

getBufferSize	back to summary
public int getBufferSize() Calculate the current buffer size.

getBufferSizeLimit	back to summary
public final int getBufferSizeLimit() Return the configured buffer size limit.

getExpectedContentLength	back to summary
public Integer getExpectedContentLength() Get the expected content length of the currently buffered, incomplete STOMP frame. Annotations @Nullable

getExpectedContentLength

back to summary

public Integer getExpectedContentLength()

Get the expected content length of the currently buffered, incomplete STOMP frame.

Annotations

@Nullable

getStompDecoder	back to summary
public final StompDecoder getStompDecoder() Return the wrapped `StompDecoder`.