com.cloudera.sqoop.mapreduce.TextExportMapper.java Source code

Introduction

Here is the source code for com.cloudera.sqoop.mapreduce.TextExportMapper.java

Source

/**
 * Licensed to Cloudera, Inc. under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  Cloudera, Inc. 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 com.cloudera.sqoop.mapreduce;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper.Context;
import org.apache.hadoop.util.ReflectionUtils;

import com.cloudera.sqoop.lib.RecordParser;
import com.cloudera.sqoop.lib.SqoopRecord;

/**
 * Converts an input record from a string representation to a parsed Sqoop
 * record and emits that DBWritable to the OutputFormat for writeback to the
 * database.
 */
public class TextExportMapper extends AutoProgressMapper<LongWritable, Text, SqoopRecord, NullWritable> {

    private SqoopRecord recordImpl;

    public TextExportMapper() {
    }

    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);
        }
    }

    public void map(LongWritable key, Text val, Context context) throws IOException, InterruptedException {
        try {
            recordImpl.parse(val);
            context.write(recordImpl, NullWritable.get());
        } catch (RecordParser.ParseError pe) {
            throw new IOException("Could not parse record: " + val, pe);
        }
    }
}