code: public void save(DbSession dbSession, String key, String value) {
      checkKey(key);
      checkArgument(value != null && !value.isEmpty(), "value can't be null nor empty");
  
      InternalPropertiesMapper mapper = getMapper(dbSession);
      mapper.deleteByKey(key);
      long now = system2.now();
      if (mustsBeStoredInClob(value)) {
        mapper.insertAsClob(key, value, now);
      } else {
        mapper.insertAsText(key, value, now);
      }
    }
docs: Save a property which value is not empty.
  <p>Value can't be {@code null} but can have any size except 0.</p>
  
  @throws IllegalArgumentException if {@code key} or {@code value} is {@code null} or empty.
  
  @see #saveAsEmpty(DbSession, String)