| /** |
| * 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.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.Text; |
| 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.hcatalog.common.HCatConstants; |
| import org.apache.hcatalog.data.HCatRecord; |
| import org.apache.hcatalog.mapreduce.HCatInputFormat; |
| import org.apache.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 SimpleRead extends Configured implements Tool { |
| |
| private static final String TABLE_NAME = "studenttab10k"; |
| private static final String TAB = "\t"; |
| |
| public static class Map |
| extends Mapper<WritableComparable, HCatRecord, Text, IntWritable> { |
| |
| String name; |
| int age; |
| double gpa; |
| |
| @Override |
| protected void map(WritableComparable key, HCatRecord value, |
| org.apache.hadoop.mapreduce.Mapper<WritableComparable, HCatRecord, |
| Text, IntWritable>.Context context) |
| throws IOException, InterruptedException { |
| name = (String) value.get(0); |
| age = (Integer) value.get(1); |
| gpa = (Double) value.get(2); |
| context.write(new Text(name), new IntWritable(age)); |
| |
| } |
| } |
| |
| 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, "SimpleRead"); |
| HCatInputFormat.setInput(job, InputJobInfo.create( |
| dbName, tableName, null)); |
| // initialize HCatOutputFormat |
| |
| job.setInputFormatClass(HCatInputFormat.class); |
| job.setOutputFormatClass(TextOutputFormat.class); |
| job.setJarByClass(SimpleRead.class); |
| job.setMapperClass(Map.class); |
| job.setOutputKeyClass(Text.class); |
| job.setOutputValueClass(IntWritable.class); |
| 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 SimpleRead(), args); |
| System.exit(exitCode); |
| } |
| } |