Java tutorial
/* * Licensed 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 clustering.link_back.step1; import clustering.Utils.MapReduceUtils; import clustering.link_back.JoinPartitioner; import clustering.link_back.io.Step1KeyWritable; 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.mapreduce.Job; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.input.KeyValueTextInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; import org.apache.hadoop.util.Tool; import org.apache.hadoop.util.ToolRunner; /** * WorkflowDriver class to join the simhash intermediate output and the mst output. * * @author edwardlol * Created by edwardlol on 2017/4/27. */ public class Driver extends Configured implements Tool { //~ Methods --------------------------------------------------------------- @Override public int run(String[] args) throws Exception { Job job = configJob(args); return job.waitForCompletion(true) ? 0 : 1; } public Job configJob(String[] args) throws Exception { if (args.length < 3) { System.err.printf("usage: %s mst_result_dir simhash_result_file output_dir\n", getClass().getSimpleName()); System.exit(1); } Configuration conf = getConf(); conf = MapReduceUtils.initConf(conf); Job job = Job.getInstance(conf, "link back step 1 job"); job.setJarByClass(Driver.class); FileInputFormat.addInputPath(job, new Path(args[0])); FileInputFormat.addInputPath(job, new Path(args[1])); job.setInputFormatClass(KeyValueTextInputFormat.class); job.setMapperClass(SetKeyMapper.class); job.setMapOutputKeyClass(Step1KeyWritable.class); job.setMapOutputValueClass(Text.class); job.setPartitionerClass(JoinPartitioner.class); job.setGroupingComparatorClass(Step1GroupComparator.class); job.setReducerClass(JoinReducer.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(IntWritable.class); FileOutputFormat.setOutputPath(job, new Path(args[2])); return job; } //~ Entrance -------------------------------------------------------------- public static void main(String[] args) throws Exception { Configuration configuration = new Configuration(); System.exit(ToolRunner.run(configuration, new Driver(), args)); } } // End WorkflowDriver.java