java 在 Netty 中关闭客户端连接
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/31200365/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Close client connection in Netty
提问by Hyman Daniel
I have simple Netty client/server app. in server side I check if client connect from right host or not and if it's not correct, close the client's connection. in server side I use this code:
我有简单的 Netty 客户端/服务器应用程序。在服务器端，我检查客户端是否从正确的主机连接，如果不正确，关闭客户端的连接。在服务器端我使用这个代码：
@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
String remoteAddress = ctx.channel().remoteAddress().toString();
if(!"/127.0.0.1:42477".equals(remoteAddress)) {
ctx.writeAndFlush("Not correct remote address! Connection closed");
ctx.close();
}
System.out.println(remoteAddress);
}
and in client side this one:
在客户端这个：
@Override
protected void channelRead0(ChannelHandlerContext ctx, String data) throws Exception {
try {
System.err.println(data);
} finally {
ReferenceCountUtil.retain(data);
}
}
but I can't get the message from server side in ctx.writeAndFlush() and client side shutdown with exception:
但我无法在 ctx.writeAndFlush() 和客户端关闭中从服务器端获取消息，但异常：
java.io.IOException: Соединение сброшено другой стороной(TRANSLATION: Connection reset from the other side)
at sun.nio.ch.FileDispatcherImpl.read0(Native Method)
at sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:39)
at sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:223)
at sun.nio.ch.IOUtil.read(IOUtil.java:192)
at sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:379)
at io.netty.buffer.UnpooledUnsafeDirectByteBuf.setBytes(UnpooledUnsafeDirectByteBuf.java:447)
at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:881)
at io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:242)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:119)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:511)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:468)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:382)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:354)
at io.netty.util.concurrent.SingleThreadEventExecutor.run(SingleThreadEventExecutor.java:111)
at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)
at java.lang.Thread.run(Thread.java:745)
how I can close client connection in rigth way? I'm newbe in netty
如何以正确的方式关闭客户端连接？我是 netty 的新手
回答by izstas
ctx.writeAndFlushis asynchronous and therefore may return beforethe data is actually written to the channel. However, it returns a ChannelFuture, which lets you add a listener which will be notified when the operation is complete. To make sure the channel is closed only after the data has been written, you can do the following:
ctx.writeAndFlush是异步的，因此可能会在数据实际写入通道之前返回。但是，它返回一个ChannelFuture，它允许您添加一个侦听器，该侦听器将在操作完成时收到通知。要确保仅在写入数据后关闭通道，您可以执行以下操作：
ctx.writeAndFlush("Not correct remote address! Connection closed")
.addListener(ChannelFutureListener.CLOSE);
