code: public static String getValue(final MetaConfig metaConfig, final String key) throws NotAvailableException {
          for (EntryType.Entry entry : metaConfig.getEntryList()) {
              if (entry.getKey().equals(key)) {
                  if (!entry.getValue().isEmpty()) {
                      return entry.getValue();
                  }
              }
          }
          throw new NotAvailableException("value for Key[" + key + "]");
      }
docs: Resolves the key to the value entry of the given meta config.
  
  @param metaConfig key value set
  @param key the key to resolve
  @return the related value of the given key.
  @throws org.openbase.jul.exception.NotAvailableException si thrown if not value for the given key could be resolved.