org.apache.bookkeeper.util.NettyChannelUtil Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
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*/
package org.apache.bookkeeper.util;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelOutboundInvoker;
import io.netty.channel.VoidChannelPromise;
/**
* Contains utility methods for working with Netty Channels.
*/
public final class NettyChannelUtil {
private NettyChannelUtil() {
}
/**
* Write and flush the message to the channel.
*
* The promise is an instance of {@link VoidChannelPromise} that properly propagates exceptions up to the pipeline.
* Netty has many ad-hoc optimization if the promise is an instance of {@link VoidChannelPromise}.
* Lastly, it reduces pollution of useless {@link io.netty.channel.ChannelPromise} objects created
* by the default write and flush method {@link ChannelOutboundInvoker#writeAndFlush(Object)}.
* See https://stackoverflow.com/q/54169262 and https://stackoverflow.com/a/9030420 for more details.
*
* @param ctx channel's context
* @param msg buffer to write in the channel
*/
public static void writeAndFlushWithVoidPromise(ChannelOutboundInvoker ctx, Object msg) {
ctx.writeAndFlush(msg, ctx.voidPromise());
}
/**
* Write and flush the message to the channel and the close the channel.
*
* This method is particularly helpful when the connection is in an invalid state
* and therefore a new connection must be created to continue.
*
* @param ctx channel's context
* @param msg buffer to write in the channel
*/
public static void writeAndFlushWithClosePromise(ChannelOutboundInvoker ctx, Object msg) {
ctx.writeAndFlush(msg).addListener(ChannelFutureListener.CLOSE);
}
}