DelimiterBasedFrameDecoder 自定义分隔符
给Server发送多条信息,但是server会讲多条信息合并为一条。这时候我们需要对发生的消息指定分割,让client和server都知道这些消息是一条一条的
//设置连接符/分隔符,换行显示
ByteBuf buf = Unpooled.copiedBuffer("$_".getBytes());
//DelimiterBasedFrameDecoder:自定义分隔符
sc.pipeline().addLast(new DelimiterBasedFrameDecoder(1024, buf)); //设置为字符串形式的解码:将传递的buf改为String
sc.pipeline().addLast(new StringDecoder()); //处理消息
sc.pipeline().addLast(new ClientHandler());
整体代码:
public static void main(String[] args) throws InterruptedException { EventLoopGroup worker = new NioEventLoopGroup();
Bootstrap b = new Bootstrap();
b.group(worker)
.channel(NioSocketChannel.class)
.handler(new ChannelInitializer<SocketChannel>() { @Override
protected void initChannel(SocketChannel sc) throws Exception {
// TODO Auto-generated method stub
//设置连接符/分隔符,换行显示
ByteBuf buf = Unpooled.copiedBuffer("$_".getBytes());
//DelimiterBasedFrameDecoder:自定义分隔符
sc.pipeline().addLast(new DelimiterBasedFrameDecoder(1024, buf)); //设置为字符串形式的解码:将传递的buf改为String
sc.pipeline().addLast(new StringDecoder()); sc.pipeline().addLast(new ClientHandler());
}
});
//连接端口
ChannelFuture cf = b.connect("127.0.0.1", 8765).sync();
cf.channel().writeAndFlush(Unpooled.copiedBuffer("aaa$_".getBytes()));
cf.channel().writeAndFlush(Unpooled.copiedBuffer("bbbbb$_".getBytes()));
cf.channel().writeAndFlush(Unpooled.copiedBuffer("cccccccc$_".getBytes())); cf.channel().closeFuture().sync();
worker.shutdownGracefully(); }
FixedLengthFrameDecoder 定长消息:及发送的消息需要一定的长度,当长度不够时,剩下的消息将会被丢弃,只能通过补空格来防止被丢弃
//自定义长度,换行显示
//设置每次发送长度为5个字符
sc.pipeline().addLast(new FixedLengthFrameDecoder(5)); //设置为字符串形式的解码:将传递的buf改为String
sc.pipeline().addLast(new StringDecoder()); //处理消息
sc.pipeline().addLast(new ClientHandler());
完整代码
public static void main(String[] args) throws InterruptedException { EventLoopGroup worker = new NioEventLoopGroup();
Bootstrap b = new Bootstrap();
b.group(worker)
.channel(NioSocketChannel.class)
.handler(new ChannelInitializer<SocketChannel>() { @Override
protected void initChannel(SocketChannel sc) throws Exception {
// TODO Auto-generated method stub
//设置定长长度为5个字符,换行显示
//每次发送消息的长度需要是5的倍数
sc.pipeline().addLast(new FixedLengthFrameDecoder(5)); //设置为字符串形式的解码:将传递的buf改为String
sc.pipeline().addLast(new StringDecoder()); sc.pipeline().addLast(new ClientHandler());
}
});
//连接端口
ChannelFuture cf = b.connect("127.0.0.1", 8765).sync(); //打印为:aaaaa
//打印为:bb被丢弃,未满5个长度
cf.channel().writeAndFlush(Unpooled.copiedBuffer("aaaaabb".getBytes())); //打印为:bbbbb
//打印完:ccccc
cf.channel().writeAndFlush(Unpooled.copiedBuffer("bbbbbccccc".getBytes())); //打印为:ddddd
//打印完:dd空格空格空格
cf.channel().writeAndFlush(Unpooled.copiedBuffer("ddddddd
".getBytes())); cf.channel().closeFuture().sync();
worker.shutdownGracefully(); }