code: public static void deleteValue(String keyName, String valueName) throws RegistryException {
          try (Key key = Key.open(keyName, KEY_WRITE)) {
              checkError(invoke(Methods.REG_DELETE_VALUE.get(), key.id, toByteArray(valueName)));
          }
      }
docs: Deletes a value within a key.
  
  @param keyName Name of the key, which contains the value to delete.
  @param valueName Name of the value to delete.
  @throws RegistryException