Java tutorial
/* * Copyright 2014-2019 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.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; /** * Provides the {@link org.springframework.integration.scheduling.PollerMetadata} options * for the Messaging annotations for polled endpoints. It is an analogue of the XML * {@code <poller/>} element, but provides only simple attributes. If the * {@link org.springframework.integration.scheduling.PollerMetadata} requires more options * (e.g. Transactional and other Advices) or {@code initialDelay, receiveTimeout} etc, the * {@link org.springframework.integration.scheduling.PollerMetadata} should be configured * as a generic bean and its bean name can be specified as the {@code value} attribute of * this annotation. In that case, the other attributes are not allowed. * <p> * Non-reference attributes support Property Placeholder resolutions. * * @author Artem Bilan * @author Gary Russell * * @since 4.0 */ @Target({}) @Retention(RetentionPolicy.RUNTIME) public @interface Poller { /** * @return The {@link org.springframework.integration.scheduling.PollerMetadata} bean * name. */ String value() default ""; /** * @return The {@link org.springframework.scheduling.Trigger} bean name. */ String trigger() default ""; /** * @return The {@link org.springframework.core.task.TaskExecutor} bean name. */ String taskExecutor() default ""; /** * @return The maximum number of messages to receive for each poll. * Can be specified as 'property placeholder', e.g. {@code ${poller.maxMessagesPerPoll}}. * Defaults to -1 (infinity) for polling consumers and 1 for polling inbound channel adapters. */ String maxMessagesPerPoll() default ""; /** * @return The fixed delay in milliseconds to create the * {@link org.springframework.scheduling.support.PeriodicTrigger}. Can be specified as * 'property placeholder', e.g. {@code ${poller.fixedDelay}}. */ String fixedDelay() default ""; /** * @return The fixed rate in milliseconds to create the * {@link org.springframework.scheduling.support.PeriodicTrigger} with * {@code fixedRate}. Can be specified as 'property placeholder', e.g. * {@code ${poller.fixedRate}}. */ String fixedRate() default ""; /** * @return The cron expression to create the * {@link org.springframework.scheduling.support.CronTrigger}. Can be specified as * 'property placeholder', e.g. {@code ${poller.cron}}. */ String cron() default ""; /** * @return The the bean name of default error channel * for the underlying {@code MessagePublishingErrorHandler}. * @since 4.3.3 */ String errorChannel() default ""; /** * Only applies to polling consumers. * @return the time the poll thread will wait after the trigger for a new message to arrive. * Defaults to 1000 (1 second). * For polled inbound channel adapters, whether or not the polling thread blocks * is dependent on the message source implementation. * Can be specified as 'property placeholder', e.g. {@code ${my.poller.receiveTimeout}}. * @since 5.1 */ String receiveTimeout() default ""; }