com.github.ydespreaux.spring.data.elasticsearch.core.ResultsMapper Maven / Gradle / Ivy

/*
 * Copyright (C) 2018 Yoann Despréaux
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING . If not, write to the
 * Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Please send bugreports with examples or suggestions to [email protected]
 */

package com.github.ydespreaux.spring.data.elasticsearch.core;

import org.elasticsearch.common.document.DocumentField;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.springframework.lang.Nullable;

import java.util.Collection;
import java.util.List;

/**
 * ResultsMapper
 *
 * @author Yoann Despréaux
 * @since 1.0.0
 */
public interface ResultsMapper extends SearchResultMapper, GetResultMapper, MultiGetResultMapper {

    /**
     * @return the entity mapper
     */
    EntityMapper getEntityMapper();

    /**
     * @param values the document fields
     * @param clazz  the entity class
     * @param     generic method
     * @return the entity
     */
    @Nullable
     S mapEntity(Collection values, Class clazz);

    /**
     * @param source the json source
     * @param clazz  the entity class
     * @param     generic type
     * @return the entity
     */
    @Nullable
    default  S mapEntity(@Nullable String source, Class clazz) {
        if (source != null && !source.isEmpty()) {
            return getEntityMapper().mapToObject(source, clazz);
        }
        return null;
    }

    /**
     * Map a single {@link SearchHit} to an instance of the given type.
     *
     * @param searchHit must not be {@literal null}.
     * @param type      must not be {@literal null}.
     * @param        generic method
     * @return can be {@literal null} if the {@link SearchHit} does not have {@link SearchHit#hasSource() a source}.
     */
    @Nullable
     S mapEntity(SearchHit searchHit, Class type);

    /**
     * @param searchHits the hits
     * @param type       the entity class
     * @param         method generic
     * @return the list of entities
     */
     List mapEntity(SearchHits searchHits, Class type);

}