http://www.jboss.org/undertow-parent/undertow-core: Undertow (JBoss by Red Hat) 
public interface io.undertow.conduits.ByteActivityCallback
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: io.undertow.conduits.ByteActivityCallback
  super_class: java.lang.Object
{
  public abstract void activity(long);
    descriptor: (J)V
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    MethodParameters:
       Name  Flags
      bytes  
}
SourceFile: "ByteActivityCallback.java"