org.springframework.messaging.simp.stomp

Class StompDecoder

java.lang.Object

org.springframework.messaging.simp.stomp.StompDecoder

Direct Known Subclasses:

BufferingStompDecoder

public class StompDecoder
extends Object

Decodes one or more STOMP frames contained in a ByteBuffer.

An attempt is made to read all complete STOMP frames from the buffer, which could be zero, one, or more. If there is any left-over content, i.e. an incomplete STOMP frame, at the end the buffer is reset to point to the beginning of the partial content. The caller is then responsible for dealing with that incomplete content by buffering until there is more input available.

Since:

4.0

Author:

Andy Wilkinson, Rossen Stoyanchev

Constructor Summary

Constructors

Constructor and Description
StompDecoder()

Method Summary

Modifier and Type	Method and Description
List<Message<byte[]>>	decode(ByteBuffer buffer) Decodes one or more STOMP frames from the given ByteBuffer into a list of Messages.
List<Message<byte[]>>	decode(ByteBuffer buffer, MultiValueMap<String,String> headers) Decodes one or more STOMP frames from the given buffer and returns a list of Messages.
protected Integer	getContentLength(MultiValueMap<String,String> headers)
protected void	skipLeadingEol(ByteBuffer buffer) Skip one ore more EOL characters at the start of the given ByteBuffer.

Methods inherited from class java.lang.Object

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

Constructor Detail

StompDecoder

public StompDecoder()

Method Detail

decode

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

Decodes one or more STOMP frames from the given ByteBuffer into a list of Messages. If the input buffer contains any incplcontains partial STOMP frame content, or additional content with a partial STOMP frame, the buffer is reset and null is returned.

Parameters:

buffer - The buffer to decode the STOMP frame from

Returns:

the decoded messages or an empty list

decode

public List<Message<byte[]>> decode(ByteBuffer buffer,
                                    MultiValueMap<String,String> headers)

Decodes one or more STOMP frames from the given buffer and returns a list of Messages.

If the given ByteBuffer contains only partial STOMP frame content and no complete STOMP frames, an empty list is returned, and the buffer is reset to to where it was.

If the buffer contains one ore more STOMP frames, those are returned and the buffer reset to point to the beginning of the unused partial content.

The input headers map is used to store successfully parsed headers and is cleared after ever successfully read message. So when partial content is read the caller can check if a "content-length" header was read, which helps to determine how much more content is needed before the next STOMP frame can be decoded.

Parameters:

buffer - The buffer to decode the STOMP frame from

headers - an empty map that will contain successfully parsed headers in cases where the partial buffer ended with a partial STOMP frame

Returns:

decoded messages or an empty list

Throws:

StompConversionException - raised in case of decoding issues

skipLeadingEol

protected void skipLeadingEol(ByteBuffer buffer)

Skip one ore more EOL characters at the start of the given ByteBuffer. Those are STOMP heartbeat frames.

getContentLength

protected Integer getContentLength(MultiValueMap<String,String> headers)