code: private static String[] getMessageTypesFromMpClass(final Class<?> mpClass) {
          final String[] classAnn = getAllMessageTypeTypeAnnotationValues(mpClass, false);
  
          // Find all of the handle methods and introspect their parameters.
          final String[] methAnn = AnnotatedMethodInvoker.introspectAnnotationMultiple(mpClass, MessageHandler.class).stream()
                  .map(m -> getAllMessageTypeTypeAnnotationValues(m.getParameterTypes()[0], false)).map(Arrays::stream).flatMap(v -> v)
                  .toArray(String[]::new);
  
          return Arrays.stream(new String[][] { classAnn, methAnn }).map(Arrays::stream).flatMap(v -> v).toArray(String[]::new);
      }
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