/*
 * Copyright 2016 requery.io
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.requery.sql;

import io.requery.meta.Attribute;
import io.requery.query.Expression;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Set;

class EntityResultReader<E extends S, S> implements ResultReader<E> {

    private final EntityReader<E, S> reader;
    private final Attribute[] attributes;

    /**
     * Creates a new reader instance for transforming a result to an entity.
     *
     * @param reader     to use
     * @param attributes this is used instead of the set in
     *                   {@link ResultReader#read(ResultSet, Set)} for performance reasons
     */
    EntityResultReader(EntityReader<E, S> reader, Attribute[] attributes) {
        this.reader = reader;
        this.attributes = attributes;
    }

    @Override
    public E read(ResultSet results, Set<? extends Expression<?>> selection) throws SQLException {
        return reader.fromResult(null, results, attributes);
    }
}