cherry.foundation.etl.ExtractorResultSetExtractor.java Source code

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Here is the source code for cherry.foundation.etl.ExtractorResultSetExtractor.java

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/*
 * Copyright 2014,2015 agwlvssainokuni
 *
 * 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 cherry.foundation.etl;

import java.io.IOException;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;

import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.ResultSetExtractor;

public class ExtractorResultSetExtractor implements ResultSetExtractor<Long> {

    private Consumer consumer;

    private Limiter limiter;

    public ExtractorResultSetExtractor(Consumer consumer, Limiter limiter) {
        this.consumer = consumer;
        this.limiter = limiter;
    }

    @Override
    public Long extractData(ResultSet rs) throws SQLException, DataAccessException {
        try {

            ResultSetMetaData metaData = rs.getMetaData();
            Column[] col = new Column[metaData.getColumnCount()];
            for (int i = 1; i <= col.length; i++) {
                col[i - 1] = new Column();
                col[i - 1].setType(metaData.getColumnType(i));
                col[i - 1].setLabel(metaData.getColumnLabel(i));
            }

            consumer.begin(col);

            long count;
            for (count = 0L; rs.next(); count++) {

                Object[] record = new Object[col.length];
                for (int i = 1; i <= record.length; i++) {
                    record[i - 1] = rs.getObject(i);
                }

                consumer.consume(record);
                limiter.tick();
            }

            consumer.end();
            return count;

        } catch (IOException ex) {
            throw new IllegalStateException(ex);
        }
    }

}