/*
* Copyright (c) 2008-2017, Hazelcast, Inc. All Rights Reserved.
*
* 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 com.hazelcast.internal.networking;
import java.nio.ByteBuffer;
/**
* Responsible for writing {@link OutboundFrame} to a {@link ByteBuffer}.
*
* Each {@link ChannelWriter} will have its own {@link ChannelOutboundHandler} instance. Therefor it doesn't need
* to be thread-safe.
*
* For more information about the ChannelOutboundHandler (and handlers in generally), have a look at the
* {@link ChannelInboundHandler}.
*
* @param <F>
* @see EventLoopGroup
*/
public interface ChannelOutboundHandler<F extends OutboundFrame> {
/**
* A callback to indicate that the Frame should be written to the destination ByteBuffer.
*
* It could be that a Frame is too big to fit into the ByteBuffer in 1 go; in that case this call will be made
* for the same Frame multiple times until write returns true. It is up to the Frame to track where
* it needs to continue.
*
* @param frame the Frame to write
* @param dst the destination ByteBuffer
* @return true if the Frame is completely written
* @throws Exception if something fails while writing to ByteBuffer. When an exception is thrown, the TcpIpConnection is
* closed. There is no point continuing with a potentially corrupted stream.
*/
boolean onWrite(F frame, ByteBuffer dst) throws Exception;
}