/**
 * KeyMatchHelper is a helper class for KeyMatch feature.
 * It manages KeyMatch instances and provides methods to build queries for boosting documents.
 */
public class KeyMatchHelper extends AbstractConfigHelper {
    private static final Logger logger = LogManager.getLogger(KeyMatchHelper.class);

    /**
     * Default constructor.
     */
    public KeyMatchHelper() {
        super();
    }

    /**