code: public List<FunctionDescriptor> buildListing() {
          List<FunctionDescriptor> listing = new ArrayList<>();
  
          for (Map.Entry<String, Method> entry : m_functions.entrySet()) {
              FunctionDescriptor descriptor = new FunctionDescriptor(entry.getKey().toUpperCase());
              listing.add(descriptor);
          }
  
          Collections.sort(listing, new Comparator<FunctionDescriptor>() {
              @Override
              public int compare(FunctionDescriptor f1, FunctionDescriptor f2) {
                  return f1.m_name.compareTo(f2.m_name);
              }
          });
  
          return listing;
      }
docs: Builds a listing of all functions sorted A-Z. Unlike the Python port, this only returns function names as Java
  doesn't so easily support reading of docstrings and Java 7 doesn't provide access to parameter names.
  @return the function listing