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.handler.codec.http2.Http2PingFrame extends io.netty.handler.codec.http2.Http2Frame
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: io.netty.handler.codec.http2.Http2PingFrame
  super_class: java.lang.Object
{
  public abstract boolean ack();
    descriptor: ()Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract long content();
    descriptor: ()J
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
}
SourceFile: "Http2PingFrame.java"