org.apache.sqoop.mapreduce.AvroImportMapper.java Source code

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Here is the source code for org.apache.sqoop.mapreduce.AvroImportMapper.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.sqoop.mapreduce;

import java.io.IOException;
import java.math.BigDecimal;
import java.nio.ByteBuffer;
import java.sql.Date;
import java.sql.SQLException;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.Map;
import org.apache.avro.Schema;
import org.apache.avro.generic.GenericData;
import org.apache.avro.generic.GenericRecord;
import org.apache.avro.mapred.AvroWrapper;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.BytesWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import com.cloudera.sqoop.lib.BlobRef;
import com.cloudera.sqoop.lib.ClobRef;
import com.cloudera.sqoop.lib.LargeObjectLoader;
import com.cloudera.sqoop.lib.SqoopRecord;
import com.cloudera.sqoop.mapreduce.AutoProgressMapper;

/**
 * Imports records by transforming them to Avro records in an Avro data file.
 */
public class AvroImportMapper
        extends AutoProgressMapper<LongWritable, SqoopRecord, AvroWrapper<GenericRecord>, NullWritable> {

    private final AvroWrapper<GenericRecord> wrapper = new AvroWrapper<GenericRecord>();
    private Schema schema;
    private LargeObjectLoader lobLoader;
    private boolean bigDecimalFormatString;

    @Override
    protected void setup(Context context) throws IOException, InterruptedException {
        Configuration conf = context.getConfiguration();
        schema = AvroJob.getMapOutputSchema(conf);
        lobLoader = new LargeObjectLoader(conf, FileOutputFormat.getWorkOutputPath(context));
        bigDecimalFormatString = conf.getBoolean(ImportJobBase.PROPERTY_BIGDECIMAL_FORMAT,
                ImportJobBase.PROPERTY_BIGDECIMAL_FORMAT_DEFAULT);
    }

    @Override
    protected void map(LongWritable key, SqoopRecord val, Context context)
            throws IOException, InterruptedException {

        try {
            // Loading of LOBs was delayed until we have a Context.
            val.loadLargeObjects(lobLoader);
        } catch (SQLException sqlE) {
            throw new IOException(sqlE);
        }

        wrapper.datum(toGenericRecord(val));
        context.write(wrapper, NullWritable.get());
    }

    @Override
    protected void cleanup(Context context) throws IOException {
        if (null != lobLoader) {
            lobLoader.close();
        }
    }

    private GenericRecord toGenericRecord(SqoopRecord val) {
        Map<String, Object> fieldMap = val.getFieldMap();
        GenericRecord record = new GenericData.Record(schema);
        for (Map.Entry<String, Object> entry : fieldMap.entrySet()) {
            record.put(entry.getKey(), toAvro(entry.getValue()));
        }
        return record;
    }

    /**
     * Convert the Avro representation of a Java type (that has already been
     * converted from the SQL equivalent).
     * @param o
     * @return
     */
    private Object toAvro(Object o) {
        if (o instanceof BigDecimal) {
            if (bigDecimalFormatString) {
                return ((BigDecimal) o).toPlainString();
            } else {
                return o.toString();
            }
        } else if (o instanceof Date) {
            return ((Date) o).getTime();
        } else if (o instanceof Time) {
            return ((Time) o).getTime();
        } else if (o instanceof Timestamp) {
            return ((Timestamp) o).getTime();
        } else if (o instanceof BytesWritable) {
            BytesWritable bw = (BytesWritable) o;
            return ByteBuffer.wrap(bw.getBytes(), 0, bw.getLength());
        } else if (o instanceof BlobRef) {
            BlobRef br = (BlobRef) o;
            // If blob data is stored in an external .lob file, save the ref file
            // as Avro bytes. If materialized inline, save blob data as Avro bytes.
            byte[] bytes = br.isExternal() ? br.toString().getBytes() : br.getData();
            return ByteBuffer.wrap(bytes);
        } else if (o instanceof ClobRef) {
            throw new UnsupportedOperationException("ClobRef not suported");
        }
        // primitive types (Integer, etc) are left unchanged
        return o;
    }

}