docs: private void addExtraClasses(final InMemoryJarfile jarOutput) throws VoltCompilerException {
  
          List<String> addedClasses = new ArrayList<>();
  
          for (String className : m_addedClasses) {
              /*
               * Only add the class if it isn't already in the output jar.
               * The jar will be pre-populated when performing an automatic
               * catalog version upgrade.
               */
              if (!jarOutput.containsKey(className)) {
                  try {
                      Class<?> clz = Class.forName(className, true, m_classLoader);
  
                      if (addClassToJar(jarOutput, clz)) {
                          addedClasses.add(className);
                      }
  
                  }
                  catch (Exception e) {
                      String msg = "Class %s could not be loaded/found/added to the jar.";
                      msg = String.format(msg, className);
                      throw new VoltCompilerException(msg);
                  }
                  // reset the added classes to the actual added classes
              }
          }
          m_addedClasses = addedClasses.toArray(new String[0]);
      }