/**
* 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.hive.hcatalog.utils;
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.hive.hcatalog.common.HCatConstants;
import org.apache.hive.hcatalog.data.DefaultHCatRecord;
import org.apache.hive.hcatalog.data.HCatRecord;
import org.apache.hive.hcatalog.mapreduce.HCatInputFormat;
import org.apache.hive.hcatalog.mapreduce.InputJobInfo;
/**
* This is a map reduce test for testing hcat which goes against the "numbers"
* table. It performs a group by on the first column and a SUM operation on the
* other columns. This is to simulate a typical operation in a map reduce program
* to test that hcat hands the right data to the map reduce program
*
* Usage: hadoop jar sumnumbers <serveruri> <output dir> <-libjars hive-hcat jar>
The <tab|ctrla> argument controls the output delimiter
The hcat jar location should be specified as file://<full path to jar>
*/
public class ReadText extends Configured implements Tool {
public static class Map
extends Mapper<WritableComparable, HCatRecord, IntWritable, HCatRecord> {
byte t;
short si;
int i;
long b;
float f;
double d;
String s;
@Override
protected void map(WritableComparable key, HCatRecord value,
org.apache.hadoop.mapreduce.Mapper<WritableComparable, HCatRecord,
IntWritable, HCatRecord>.Context context)
throws IOException, InterruptedException {
t = (Byte) value.get(0);
si = (Short) value.get(1);
i = (Integer) value.get(2);
b = (Long) value.get(3);
f = (Float) value.get(4);
d = (Double) value.get(5);
s = (String) value.get(6);
HCatRecord record = new DefaultHCatRecord(7);
record.set(0, t);
record.set(1, si);
record.set(2, i);
record.set(3, b);
record.set(4, f);
record.set(5, d);
record.set(6, s);
context.write(null, record);
}
}
public int run(String[] args) throws Exception {
Configuration conf = getConf();
args = new GenericOptionsParser(conf, args).getRemainingArgs();
String serverUri = args[0];
String tableName = args[1];
String outputDir = args[2];
String dbName = null;
String principalID = System.getProperty(HCatConstants.HCAT_METASTORE_PRINCIPAL);
if (principalID != null)
conf.set(HCatConstants.HCAT_METASTORE_PRINCIPAL, principalID);
Job job = new Job(conf, "ReadText");
HCatInputFormat.setInput(job, InputJobInfo.create(
dbName, tableName, null));
// initialize HCatOutputFormat
job.setInputFormatClass(HCatInputFormat.class);
job.setOutputFormatClass(TextOutputFormat.class);
job.setJarByClass(ReadText.class);
job.setMapperClass(Map.class);
job.setOutputKeyClass(IntWritable.class);
job.setOutputValueClass(HCatRecord.class);
job.setNumReduceTasks(0);
FileOutputFormat.setOutputPath(job, new Path(outputDir));
return (job.waitForCompletion(true) ? 0 : 1);
}
public static void main(String[] args) throws Exception {
int exitCode = ToolRunner.run(new ReadText(), args);
System.exit(exitCode);
}
}