/*
* Copyright 2002-2016 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
*
* http://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.messaging;
/**
* Defines methods for sending messages.
*
* @author Mark Fisher
* @since 4.0
*/
@FunctionalInterface
public interface MessageChannel {
/**
* Constant for sending a message without a prescribed timeout.
*/
long INDEFINITE_TIMEOUT = -1;
/**
* Send a {@link Message} to this channel. If the message is sent successfully,
* the method returns {@code true}. If the message cannot be sent due to a
* non-fatal reason, the method returns {@code false}. The method may also
* throw a RuntimeException in case of non-recoverable errors.
* <p>This method may block indefinitely, depending on the implementation.
* To provide a maximum wait time, use {@link #send(Message, long)}.
* @param message the message to send
* @return whether or not the message was sent
*/
default boolean send(Message<?> message) {
return send(message, INDEFINITE_TIMEOUT);
}
/**
* Send a message, blocking until either the message is accepted or the
* specified timeout period elapses.
* @param message the message to send
* @param timeout the timeout in milliseconds or {@link #INDEFINITE_TIMEOUT}
* @return {@code true} if the message is sent, {@code false} if not
* including a timeout of an interrupt of the send
*/
boolean send(Message<?> message, long timeout);
}