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

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Here is the source code for org.apache.sqoop.mapreduce.GenericRecordExportMapper.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 com.cloudera.sqoop.lib.SqoopRecord;
import com.cloudera.sqoop.mapreduce.AutoProgressMapper;
import com.cloudera.sqoop.orm.ClassWriter;
import org.apache.avro.Conversions;
import org.apache.avro.Schema;
import org.apache.avro.generic.GenericData;
import org.apache.avro.generic.GenericRecord;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.DefaultStringifier;
import org.apache.hadoop.io.MapWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.util.ReflectionUtils;
import org.apache.sqoop.avro.AvroUtil;

import java.io.IOException;
import java.util.Map;

/**
 * Exports records (type GenericRecord) from a data source.
 */
public class GenericRecordExportMapper<K, V> extends AutoProgressMapper<K, V, SqoopRecord, NullWritable> {

    public static final String AVRO_COLUMN_TYPES_MAP = "sqoop.avro.column.types.map";

    protected MapWritable columnTypes;

    private SqoopRecord recordImpl;

    @Override
    protected void setup(Context context) throws IOException, InterruptedException {
        super.setup(context);

        Configuration conf = context.getConfiguration();

        // Instantiate a copy of the user's class to hold and parse the record.
        String recordClassName = conf.get(ExportJobBase.SQOOP_EXPORT_TABLE_CLASS_KEY);
        if (null == recordClassName) {
            throw new IOException(
                    "Export table class name (" + ExportJobBase.SQOOP_EXPORT_TABLE_CLASS_KEY + ") is not set!");
        }

        try {
            Class cls = Class.forName(recordClassName, true, Thread.currentThread().getContextClassLoader());
            recordImpl = (SqoopRecord) ReflectionUtils.newInstance(cls, conf);
        } catch (ClassNotFoundException cnfe) {
            throw new IOException(cnfe);
        }

        if (null == recordImpl) {
            throw new IOException("Could not instantiate object of type " + recordClassName);
        }

        columnTypes = DefaultStringifier.load(conf, AVRO_COLUMN_TYPES_MAP, MapWritable.class);

        // Add decimal support
        GenericData.get().addLogicalTypeConversion(new Conversions.DecimalConversion());
    }

    protected SqoopRecord toSqoopRecord(GenericRecord record) throws IOException {
        Schema avroSchema = record.getSchema();
        for (Map.Entry<Writable, Writable> e : columnTypes.entrySet()) {
            String columnName = e.getKey().toString();
            String columnType = e.getValue().toString();
            String cleanedCol = ClassWriter.toIdentifier(columnName);
            Schema.Field field = getFieldIgnoreCase(avroSchema, cleanedCol);
            if (null == field) {
                throw new IOException("Cannot find field " + cleanedCol + " in Avro schema " + avroSchema);
            }

            Object avroObject = record.get(field.name());
            Object fieldVal = AvroUtil.fromAvro(avroObject, field.schema(), columnType);
            recordImpl.setField(cleanedCol, fieldVal);
        }
        return recordImpl;
    }

    private static Schema.Field getFieldIgnoreCase(Schema avroSchema, String fieldName) {
        for (Schema.Field field : avroSchema.getFields()) {
            if (field.name().equalsIgnoreCase(fieldName)) {
                return field;
            }
        }
        return null;
    }

}