com.cloudera.sqoop.testutil.ExplicitSetMapper.java Source code

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Here is the source code for com.cloudera.sqoop.testutil.ExplicitSetMapper.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 com.cloudera.sqoop.testutil;

import java.io.IOException;

import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import com.cloudera.sqoop.lib.SqoopRecord;
import org.apache.hadoop.util.ReflectionUtils;

/**
 * Test harness mapper. Instantiate the user's specific type, explicitly
 * set the value of a field with setField(), and read the field value
 * back via the field map. Throw an IOException if it doesn't get set
 * correctly.
 */
public class ExplicitSetMapper extends MapReduceBase implements Mapper<LongWritable, Text, Text, NullWritable> {

    public static final Log LOG = LogFactory.getLog(ExplicitSetMapper.class.getName());

    public static final String USER_TYPE_NAME_KEY = "sqoop.user.class";
    public static final String SET_COL_KEY = "sqoop.explicit.set.col";
    public static final String SET_VAL_KEY = "sqoop.explicit.set.val";

    private SqoopRecord userRecord;
    private String setCol;
    private String setVal;

    public void configure(JobConf job) {
        String userTypeName = job.get(USER_TYPE_NAME_KEY);
        if (null == userTypeName) {
            throw new RuntimeException("Unconfigured parameter: " + USER_TYPE_NAME_KEY);
        }

        setCol = job.get(SET_COL_KEY);
        setVal = job.get(SET_VAL_KEY);

        LOG.info("User type name set to " + userTypeName);
        LOG.info("Will try to set col " + setCol + " to " + setVal);

        this.userRecord = null;

        try {
            Configuration conf = new Configuration();
            Class userClass = Class.forName(userTypeName, true, Thread.currentThread().getContextClassLoader());
            this.userRecord = (SqoopRecord) ReflectionUtils.newInstance(userClass, conf);
        } catch (ClassNotFoundException cnfe) {
            // handled by the next block.
            LOG.error("ClassNotFound exception: " + cnfe.toString());
        } catch (Exception e) {
            LOG.error("Got an exception reflecting user class: " + e.toString());
        }

        if (null == this.userRecord) {
            LOG.error("Could not instantiate user record of type " + userTypeName);
            throw new RuntimeException("Could not instantiate user record of type " + userTypeName);
        }
    }

    public void map(LongWritable key, Text val, OutputCollector<Text, NullWritable> out, Reporter r)
            throws IOException {

        // Try to set the field.
        userRecord.setField(setCol, setVal);
        Map<String, Object> fieldVals = userRecord.getFieldMap();
        if (!fieldVals.get(setCol).equals(setVal)) {
            throw new IOException("Could not set column value! Got back " + fieldVals.get(setCol));
        } else {
            LOG.info("Correctly changed value for col " + setCol + " to " + setVal);
        }
    }
}