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 interface io.netty.channel.group.ChannelGroupFutureListener extends io.netty.util.concurrent.GenericFutureListener<io.netty.channel.group.ChannelGroupFuture>
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: io.netty.channel.group.ChannelGroupFutureListener
  super_class: java.lang.Object
{
}
Signature: Ljava/lang/Object;Lio/netty/util/concurrent/GenericFutureListener<Lio/netty/channel/group/ChannelGroupFuture;>;
SourceFile: "ChannelGroupFutureListener.java"