http://netty.io/netty-all/: Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers and clients. (The Netty Project) 
public final class io.netty.example.socksproxy.SocksServerUtils
  minor version: 0
  major version: 59
  flags: flags: (0x0031) ACC_PUBLIC, ACC_FINAL, ACC_SUPER
  this_class: io.netty.example.socksproxy.SocksServerUtils
  super_class: java.lang.Object
{
  public static void closeOnFlush(io.netty.channel.Channel);
    descriptor: (Lio/netty/channel/Channel;)V
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // io.netty.channel.Channel ch
         0: .line 28
            aload 0 /* ch */
            invokeinterface io.netty.channel.Channel.isActive:()Z
            ifeq 2
         1: .line 29
            aload 0 /* ch */
            getstatic io.netty.buffer.Unpooled.EMPTY_BUFFER:Lio/netty/buffer/ByteBuf;
            invokeinterface io.netty.channel.Channel.writeAndFlush:(Ljava/lang/Object;)Lio/netty/channel/ChannelFuture;
            getstatic io.netty.channel.ChannelFutureListener.CLOSE:Lio/netty/channel/ChannelFutureListener;
            invokeinterface io.netty.channel.ChannelFuture.addListener:(Lio/netty/util/concurrent/GenericFutureListener;)Lio/netty/channel/ChannelFuture;
            pop
         2: .line 31
      StackMap locals:
      StackMap stack:
            return
        end local 0 // io.netty.channel.Channel ch
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0    ch  Lio/netty/channel/Channel;
    MethodParameters:
      Name  Flags
      ch    

  private void <init>();
    descriptor: ()V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.example.socksproxy.SocksServerUtils this
         0: .line 33
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // io.netty.example.socksproxy.SocksServerUtils this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/example/socksproxy/SocksServerUtils;
}
SourceFile: "SocksServerUtils.java"