org.apache.hadoop.hive.jdbchandler.HiveDBOutputFormat.java Source code

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Here is the source code for org.apache.hadoop.hive.jdbchandler.HiveDBOutputFormat.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.hadoop.hive.jdbchandler;

import java.io.IOException;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;
import java.util.Properties;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hive.ql.exec.FileSinkOperator.RecordWriter;
import org.apache.hadoop.hive.ql.io.HiveOutputFormat;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.OutputFormat;
import org.apache.hadoop.util.Progressable;
import org.apache.hadoop.util.StringUtils;

/**
 * A OutputFormat that sends the reduce output to a SQL table.
 */
public class HiveDBOutputFormat<K extends Writable, V extends ResultSetWritable>
        implements HiveOutputFormat<K, V>, OutputFormat<K, V> {

    private static final Log LOG = LogFactory.getLog(HiveDBOutputFormat.class);

    /** {@inheritDoc} */
    public void checkOutputSpecs(FileSystem filesystem, JobConf job) throws IOException {
    }

    @Override
    public RecordWriter getHiveRecordWriter(JobConf job, Path finalOutPath, Class<? extends Writable> valueClass,
            boolean isCompressed, Properties tableProperties, Progressable progress) throws IOException {
        // TODO Auto-generated method stub
        DBConfiguration dbConf = new DBConfiguration(job);
        String tableName = dbConf.getOutputTableName();
        String[] fieldNames = dbConf.getOutputFieldNames();
        boolean truncate = dbConf.getTruncateBeforeInsert();
        boolean replace = dbConf.getOutputReplace();
        int batchSize = dbConf.getBatchExecuteSize();
        Connection connection = null;

        try {
            connection = new DBManager(dbConf.getConf()).getConnection();
            DatabaseMetaData dbMeta = connection.getMetaData();
            String dbProductName = dbMeta.getDatabaseProductName().toUpperCase();

            // use database product name to determine appropriate record writer.
            if (dbProductName.startsWith("ORACLE")) {
                // use Oracle-specific db writer.
                return new OracleDBRecordWriter(connection, tableName, fieldNames, truncate, replace, batchSize);
            } else if (dbProductName.startsWith("MYSQL")) {
                // use MySQL-specific db writer.
                return new MySQLDBRecordWriter(connection, tableName, fieldNames, truncate, replace, batchSize);
            } else if (dbProductName.startsWith("POSTGRESQL")) {
                // use PostgreSQL-specific db writer.
                return new PostgresDBRecordWriter(connection, tableName, fieldNames, truncate, replace, batchSize);
            } else {
                // Generic writer.
                return new DBRecordWriter(connection, tableName, fieldNames, truncate, replace, batchSize);
            }

        } catch (SQLException e) {
            LOG.error(StringUtils.stringifyException(e));
            throw new IOException(StringUtils.stringifyException(e));
        }

    }

    @Override
    public org.apache.hadoop.mapred.RecordWriter<K, V> getRecordWriter(FileSystem fileSystem, JobConf jobConf,
            String name, Progressable progressable) throws IOException {
        // TODO Auto-generated method stub
        throw new RuntimeException("Error: Hive should not invoke this method.");
    }
}