* It implements rank fusion techniques to combine results from different search engines
 * and provides a unified search interface.
 */
public class RankFusionProcessor implements AutoCloseable {

    private static final Logger logger = LogManager.getLogger(RankFusionProcessor.class);

    /** Array of rank fusion searchers available for processing search requests */
    protected RankFusionSearcher[] searchers = new RankFusionSearcher[1];

        int pageSize = 100;
        int offset = 45;
        try (RankFusionProcessor rankFusionProcessor = new RankFusionProcessor()) {
            rankFusionProcessor.setSeacher(new TestMainSearcher(allRecordCount));
            rankFusionProcessor.register(new TestSubSearcher(10, 45, 45));
            rankFusionProcessor.init();

            if (rankFusionProcessor.search(query, new TestSearchRequestParams(0, pageSize, 0),

            final OptionalThing<FessUserBean> userBean) {
        final RankFusionProcessor rankFusionProcessor = ComponentUtil.getRankFusionProcessor();
        final List<Map<String, Object>> documentItems = rankFusionProcessor.search(query, params, userBean);
        if (documentItems instanceof final QueryResponseList queryResponseList) {

import org.codelibs.fess.query.QueryFieldConfig;
import org.codelibs.fess.query.QueryProcessor;
import org.codelibs.fess.query.parser.QueryParser;
import org.codelibs.fess.rank.fusion.RankFusionProcessor;
import org.codelibs.fess.script.ScriptEngineFactory;
import org.codelibs.fess.sso.SsoManager;
import org.codelibs.fess.thumbnail.ThumbnailManager;
import org.lastaflute.core.message.MessageManager;