https://source.android.com/ 
public interface android.app.FragmentBreadCrumbs$OnBreadCrumbClickListener
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: android.app.FragmentBreadCrumbs$OnBreadCrumbClickListener
  super_class: java.lang.Object
{
  public abstract boolean onBreadCrumbClick(android.app.FragmentManager$BackStackEntry, int);
    descriptor: (Landroid/app/FragmentManager$BackStackEntry;I)Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    MethodParameters:
           Name  Flags
      backStack  
      flags      
}
SourceFile: "FragmentBreadCrumbs.java"
NestHost: android.app.FragmentBreadCrumbs
InnerClasses:
  public abstract OnBreadCrumbClickListener = android.app.FragmentBreadCrumbs$OnBreadCrumbClickListener of android.app.FragmentBreadCrumbs
  public abstract BackStackEntry = android.app.FragmentManager$BackStackEntry of android.app.FragmentManager
    RuntimeVisibleAnnotations: 
      java.lang.Deprecated()