org.springframework.integration.annotation.Splitter Maven / Gradle / Ivy
/*
* Copyright 2002-2019 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.integration.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Indicates that a method is capable of splitting a single message or message
* payload to produce multiple messages or payloads.
*
* A method annotated with @Splitter may accept a parameter of type
* {@link org.springframework.messaging.Message} or of the expected
* Message payload's type. Any type conversion supported by
* {@link org.springframework.beans.SimpleTypeConverter} will be applied to
* the Message payload if necessary. Header values can also be passed as
* Message parameters by using the
* {@link org.springframework.messaging.handler.annotation.Header @Header} parameter annotation.
*
* Return values from the annotated method may be either a Collection or Array
* with elements of any type. If the type is not a Message, each will be used
* as the payload for creating a new Message.
*
* @author Mark Fisher
* @author Gary Russell
* @author Artem Bilan
*/
@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Splitter {
/**
* Specify the channel from which this splitter will consume messages.
* If the channel does not exist, a {@code DirectChannel} with this name will be
* registered in the application context.
* @return The channel name.
*/
String inputChannel() default "";
/**
* Specify the channel to which this splitter will send any replies.
* @return The channel name.
*/
String outputChannel() default "";
/**
* Set this flag to {@code false} to prevent adding sequence related headers in this splitter.
* This can be convenient in cases where the set sequence numbers conflict with downstream
* custom aggregations. When {@code true}, existing correlation and sequence related headers
* are pushed onto a stack; downstream components, such as aggregators may pop
* the stack to revert the existing headers after aggregation.
* Defaults to {@code true}.
* Can be specified as 'property placeholder', e.g. {@code ${spring.integration.applySequence}}.
* @return the apply sequence flag.
*/
String applySequence() default "";
/**
* Specify a "chain" of {@code Advice} beans that will "wrap" the message handler.
* Only the handler is advised, not the downstream flow.
* @return the advice chain.
*/
String[] adviceChain() default { };
/**
* Specify the maximum amount of time in milliseconds to wait when sending a reply
* {@link org.springframework.messaging.Message} to the {@code outputChannel}.
* Defaults to {@code -1} - blocking indefinitely.
* It is applied only if the output channel has some 'sending' limitations, e.g.
* {@link org.springframework.integration.channel.QueueChannel} with
* fixed a 'capacity'. In this case a {@link org.springframework.messaging.MessageDeliveryException} is thrown.
* The 'sendTimeout' is ignored in case of
* {@link org.springframework.integration.channel.AbstractSubscribableChannel} implementations.
* Can be specified as 'property placeholder', e.g. {@code ${spring.integration.sendTimeout}}.
* @return The timeout for sending results to the reply target (in milliseconds)
*/
String sendTimeout() default "";
/**
* The {@link org.springframework.context.SmartLifecycle} {@code autoStartup} option.
* Can be specified as 'property placeholder', e.g. {@code ${foo.autoStartup}}.
* Defaults to {@code true}.
* @return the auto startup {@code boolean} flag.
*/
String autoStartup() default "";
/**
* Specify a {@link org.springframework.context.SmartLifecycle} {@code phase} option.
* Defaults {@code Integer.MAX_VALUE / 2} for {@link org.springframework.integration.endpoint.PollingConsumer}
* and {@code Integer.MIN_VALUE} for {@link org.springframework.integration.endpoint.EventDrivenConsumer}.
* Can be specified as 'property placeholder', e.g. {@code ${foo.phase}}.
* @return the {@code SmartLifecycle} phase.
*/
String phase() default "";
/**
* @return the {@link Poller} options for a polled endpoint
* ({@link org.springframework.integration.scheduling.PollerMetadata}).
* This attribute is an {@code array} just to allow an empty default (no poller).
* Only one {@link Poller} element is allowed.
*/
Poller[] poller() default { };
}