Package io.helidon.messaging

package io.helidon.messaging

Helidon Messaging API and runtime.

Message delivery uses a synchronous, at-least-once settlement contract. An emission returns only after every required output completes successfully. Outputs are invoked sequentially and delivery fails immediately when an output throws. Outputs completed before that failure are not rolled back, so retrying a failed emission can deliver the same message to those outputs again. Each logical channel executes at most one delivery at a time; different channels may execute concurrently. Applications and connectors must therefore tolerate duplicate delivery.

See Also:

• io.helidon.messaging.spi

Related Packages

Module	Package	Description
io.helidon	io.helidon	Startup of Helidon applications.
io.helidon.messaging	io.helidon.messaging.spi	Service provider interfaces implemented or extended by messaging transport connectors.

Class	Description
BatchDeliveryException	Structured partial or indeterminate batch delivery failure.
BatchItemOutcome	Indexed outcome of one message in a failed batch delivery.
BatchItemStatus	Outcome of one message in a failed batch delivery.
ChannelRegistry__ServiceDescriptor<T extends io.helidon.messaging.ChannelRegistry>	Service descriptor for ChannelRegistry.
ConnectorDelivery	Runtime-owned asynchronous task used by an incoming connector while its owner thread performs transport maintenance.
ConnectorDeliveryReservation	Pending message-count capacity reserved by an incoming connector before it acquires transport data.
ConsumerRegistration	Generated consumer registration contract.
DeadLetterConfig	Dead-letter delivery configuration.
DeadLetterConfig.Builder	Fluent API builder for DeadLetterConfig.
DeadLetterConfig.BuilderBase<BUILDER extends DeadLetterConfig.BuilderBase<BUILDER, PROTOTYPE>, PROTOTYPE extends DeadLetterConfig>	Fluent API builder base for DeadLetterConfig.
DeadLetterMessage<T>	Immutable message routed to a logical dead-letter channel.
Emitter<T>	Synchronous emitter for a named messaging channel.
EmitterRegistration	Generated topology metadata for an injected messaging emitter.
FailureDisposition	Terminal disposition applied after delivery attempts are exhausted.
FailurePolicy	Portable incoming delivery failure policy.
FailurePolicy.Builder	Fluent API builder for FailurePolicy.
FailurePolicy.BuilderBase<BUILDER extends FailurePolicy.BuilderBase<BUILDER, PROTOTYPE>, PROTOTYPE extends FailurePolicy>	Fluent API builder base for FailurePolicy.
IncomingConnectorContext	Runtime lifecycle and retained-delivery admission exposed to an incoming connector.
Message<T>	Message envelope with a payload, portable headers, and optional local metadata.
MessageBatch<T>	Immutable ordered delivery batch.
MessageBatchConfig<T>	Message batch construction options.
MessageBatchConfig.Builder<T>	Fluent API builder for MessageBatch.
MessageBatchConfig.BuilderBase<T, BUILDER extends MessageBatchConfig.BuilderBase<T, BUILDER, PROTOTYPE>, PROTOTYPE extends MessageBatchConfig<T>>	Fluent API builder base for MessageBatchConfig.
MessageConfig<T>	Message construction options.
MessageConfig.Builder<T>	Fluent API builder for Message.
MessageConfig.BuilderBase<T, BUILDER extends MessageConfig.BuilderBase<T, BUILDER, PROTOTYPE>, PROTOTYPE extends MessageConfig<T>>	Fluent API builder base for MessageConfig.
MessageHeader	One immutable messaging header entry.
MessageHeaders	Immutable ordered messaging headers.
MessageHeaders.Builder	Mutable messaging-header builder.
MessageHeaderValue	Immutable value used by portable messaging headers and local message metadata.
MessageHeaderValue.BinaryValue	Immutable binary messaging value.
MessageHeaderValue.BooleanValue	Boolean messaging value.
MessageHeaderValue.DecimalValue	Arbitrary-precision decimal messaging value.
MessageHeaderValue.Float32Value	32-bit IEEE 754 floating-point messaging value.
MessageHeaderValue.Float64Value	64-bit IEEE 754 floating-point messaging value.
MessageHeaderValue.IntegerValue	Arbitrary-precision integer messaging value.
MessageHeaderValue.NativeValue	Immutable transport-specific encoded messaging value.
MessageHeaderValue.NullValue	Explicit null messaging value.
MessageHeaderValue.TextValue	Text messaging value.
MessageHeaderValue.TimestampValue	Timestamp messaging value.
MessageHeaderValue.UuidValue	UUID messaging value.
MessageMetadata	Immutable exact-name, single-valued metadata local to a message envelope.
MessageMetadata.Builder	Mutable local-metadata builder.
Messaging	Declarative messaging annotations.
Messaging.Entity	Message payload parameter.
Messaging.HeaderParam	Message header parameter.
Messaging.OnFailure	Declares default delivery failure handling for the incoming channel named by Messaging.ReceiveFrom.
Messaging.ReceiveFrom	Marks a method that receives messages from a channel.
Messaging.SendTo	Target channel for the value returned by a one-to-one message processor method.
MessagingChannel<T>	Immutable typed handle identifying a channel in a MessagingGraph.
MessagingChannel.Builder<T>	Fluent API builder for MessagingChannel.
MessagingChannel.BuilderBase<T, BUILDER extends MessagingChannel.BuilderBase<T, BUILDER, PROTOTYPE>, PROTOTYPE extends MessagingChannel<T>>	Fluent API builder base for MessagingChannel.
MessagingChannel.BuilderBase.MessagingChannelImpl<T>	Generated implementation of the prototype, can be extended by descendant prototype implementations.
MessagingConfig	Messaging configuration.
MessagingConfig.Builder	Fluent API builder for MessagingGraph.
MessagingConfig.BuilderBase<BUILDER extends MessagingConfig.BuilderBase<BUILDER, PROTOTYPE>, PROTOTYPE extends MessagingConfig>	Fluent API builder base for MessagingConfig.
MessagingConfigSupport_ConfigurationProvider__ServiceDescriptor<T extends io.helidon.messaging.MessagingConfigSupport.ConfigurationProvider>	Service descriptor for MessagingConfigSupport.ConfigurationProvider.
MessagingEntryPoint	Messaging entry-point interception contracts used by generated handler registrations.
MessagingEntryPoint.BatchHandler<T>	Invocation of an explicit declarative messaging batch handler.
MessagingEntryPoint.EntryPoints	Factory used by generated code to wrap messaging handlers with entry-point interceptors.
MessagingEntryPoint.Handler<T>	Invocation of a declarative messaging handler.
MessagingEntryPointsImpl__ServiceDescriptor<T extends io.helidon.messaging.MessagingEntryPointsImpl>	Service descriptor for MessagingEntryPointsImpl.
MessagingException	Runtime exception thrown by the messaging runtime.
MessagingExecutionConfig	Optional messaging execution overrides.
MessagingExecutionConfig.Builder	Fluent API builder for MessagingExecutionConfig.
MessagingExecutionConfig.BuilderBase<BUILDER extends MessagingExecutionConfig.BuilderBase<BUILDER, PROTOTYPE>, PROTOTYPE extends MessagingExecutionConfig>	Fluent API builder base for MessagingExecutionConfig.
MessagingFailureConfig	Incoming failure-policy overrides applied to the declared policy or messaging defaults.
MessagingFailureConfig.Builder	Fluent API builder for MessagingFailureConfig.
MessagingFailureConfig.BuilderBase<BUILDER extends MessagingFailureConfig.BuilderBase<BUILDER, PROTOTYPE>, PROTOTYPE extends MessagingFailureConfig>	Fluent API builder base for MessagingFailureConfig.
MessagingGraph	One messaging topology and lifecycle.
MessagingLifecycleGuard__ServiceDescriptor<T extends io.helidon.messaging.MessagingLifecycleGuard>	Service descriptor for MessagingLifecycleGuard.
MessagingRejectedException	Message admission rejection.
MessagingRejectedException.Reason	Admission rejection reason.
MessagingRuntime	Internal synchronous runtime contract used by generated messaging emitters.
ProcessorRegistration	Generated registration for a synchronous one-to-one message processor.