Class MessageEnvelope

java.lang.Object

dev.ua.theroer.magicutils.messaging.MessageEnvelope

public final class MessageEnvelope
extends Object

Wire representation of a single message on the bus.

The envelope is transport-neutral: both the default plugin-messaging transport and the Redis transport serialize it to bytes (via MessageCodec) and reconstruct it on the receiving side. It carries the logical channel, the addressing hint, the originating MessageSource, and the already-serialized payload bytes so the transport never needs to understand the user payload type.

Constructor Summary

Constructors

Constructor	Description
MessageEnvelope(UUID id, String channel, Target target, MessageSource source, byte[] payload, long timestamp)	Creates an envelope.

Method Summary

Modifier and Type	Method	Description
boolean	acceptedBy(MessageSource self, Predicate<UUID> hostsPlayer)	Decides whether a local member should accept this envelope given the target.
String	channel()	Returns the logical channel name.
static MessageEnvelope	create(String channel, Target target, MessageSource source, byte[] payload)	Creates an envelope with a fresh id and the current timestamp.
UUID	id()	Returns the unique message id.
byte[]	payload()	Returns the serialized payload bytes.
MessageSource	source()	Returns the originating member.
Target	target()	Returns the addressing hint.
long	timestamp()	Returns the creation timestamp (epoch millis).

Methods inherited from class Object

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

Constructor Details

MessageEnvelope

public MessageEnvelope(UUID id,
 String channel,
 Target target,
 MessageSource source,
 byte[] payload,
 long timestamp)

Creates an envelope.

Parameters:

id - unique message id (for de-duplication / correlation)

channel - logical channel name

target - addressing hint

source - originating member

payload - serialized payload bytes

timestamp - epoch millis when the message was created

Method Details

create

public static MessageEnvelope create(String channel,
 Target target,
 MessageSource source,
 byte[] payload)

Creates an envelope with a fresh id and the current timestamp.

Parameters:

channel - logical channel name

target - addressing hint

source - originating member

payload - serialized payload bytes

Returns:

new envelope

id

public UUID id()

Returns the unique message id.

Returns:

message id

channel

public String channel()

Returns the logical channel name.

Returns:

channel name

target

public Target target()

Returns the addressing hint.

Returns:

target

source

public MessageSource source()

Returns the originating member.

Returns:

source

payload

public byte[] payload()

Returns the serialized payload bytes.

Returns:

payload bytes (do not mutate)

timestamp

public long timestamp()

Returns the creation timestamp (epoch millis).

Returns:

timestamp

acceptedBy

public boolean acceptedBy(MessageSource self,
 @Nullable
 Predicate<UUID> hostsPlayer)

Decides whether a local member should accept this envelope given the target.

Transports that cannot pre-filter (for example Redis pub/sub, which broadcasts to every subscriber) call this on receipt so addressing is honoured uniformly regardless of transport.

Parameters:

self - the local member

hostsPlayer - predicate answering whether the local member hosts a player id; may be null on the proxy or when player hosting is unknown

Returns:

true when the local member is an intended recipient