code: @SuppressWarnings({ "unchecked", "rawtypes" })
    public <T> void removeRegistraion(String subjectName, SubjectObserver<T> subjectObserver)
     {
        Subject subject = (Subject)this.registry.get(subjectName);
        
        if(subject == null)
           return;
        
        subject.remove(subjectObserver);
        
     }
docs: Remove an observer for a registered observer
  @param <T> the class type
  @param subjectName the subject name to remove
  @param subjectObserver the subject observer