import org.codelibs.fess.unit.UnitFessTestCase;
import org.codelibs.fess.util.ComponentUtil;
import org.opensearch.search.rescore.QueryRescorerBuilder;
import org.opensearch.search.rescore.RescorerBuilder;

public class LtrQueryRescorerTest extends UnitFessTestCase {

    private LtrQueryRescorer ltrQueryRescorer;

    @Override
    public void setUp() throws Exception {
        super.setUp();

    }

    public void test_evaluate_withParams() {
        // Test implementation that returns a RescorerBuilder
        queryRescorer = new QueryRescorer() {
            @Override
            public RescorerBuilder<?> evaluate(Map<String, Object> params) {
                if (params != null && params.containsKey("test")) {
                    return createMockRescorerBuilder();
                }
                return null;

import java.util.Map;

import org.opensearch.search.rescore.RescorerBuilder;

/**
 * Interface for query rescoring implementations.
 */
public interface QueryRescorer {
    /**
     * Evaluates the rescorer with the given parameters.
     *
     * @param params the parameters for rescoring
     * @return the rescorer builder
     */
    RescorerBuilder<?> evaluate(final Map<String, Object> params);

import org.opensearch.search.rescore.RescorerBuilder;

/**
 * Learning to Rank query rescorer implementation.
 */
public class LtrQueryRescorer implements QueryRescorer {

    /**
     * Default constructor.
     */
    public LtrQueryRescorer() {
        // Default constructor
    }

    @Override
    public RescorerBuilder<?> evaluate(final Map<String, Object> params) {

     * @return an array of rescorer builders, filtered to exclude null values
     */
    public RescorerBuilder<?>[] getRescorers(final Map<String, Object> params) {
        return queryRescorerList.stream().map(r -> r.evaluate(params)).filter(b -> b != null).toArray(n -> new RescorerBuilder<?>[n]);
    }

    /**
     * Adds a query rescorer for post-processing search results.

            public org.opensearch.search.rescore.RescorerBuilder<?> evaluate(java.util.Map<String, Object> params) {
                return null; // Return null for this test
            }
        };

        queryHelper.addQueryRescorer(mockRescorer);

        java.util.Map<String, Object> params = new java.util.HashMap<>();
        org.opensearch.search.rescore.RescorerBuilder<?>[] rescorers = queryHelper.getRescorers(params);