MAPREDUCE-7174. Mapreduce example wordmedian should handle generic options. Contributed by Fei Hui.

(cherry picked from commit 9e7196749ee025db7668c648743d1deb72d3ca28)

hadoop-mapreduce-project/hadoop-mapreduce-examples/src/main/java/org/apache/hadoop/examples/WordMedian.java

@@ -35,6 +35,7 @@ import org.apache.hadoop.mapreduce.Reducer;
 import org.apache.hadoop.mapreduce.TaskCounter;
 import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
 import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
+import org.apache.hadoop.util.GenericOptionsParser;
 import org.apache.hadoop.util.Tool;
 import org.apache.hadoop.util.ToolRunner;
 
@@ -173,13 +174,15 @@ public class WordMedian extends Configured implements Tool {
 
   @Override
   public int run(String[] args) throws Exception {
-    if (args.length != 2) {
+    Configuration conf = new Configuration();
+    String[] otherArgs =
+        new GenericOptionsParser(conf, args).getRemainingArgs();
+    if (otherArgs.length != 2) {
       System.err.println("Usage: wordmedian <in> <out>");
       return 0;
     }
 
-    setConf(new Configuration());
-    Configuration conf = getConf();
+    setConf(conf);
 
     Job job = Job.getInstance(conf, "word median");
     job.setJarByClass(WordMedian.class);
@@ -188,8 +191,8 @@ public class WordMedian extends Configured implements Tool {
     job.setReducerClass(WordMedianReducer.class);
     job.setOutputKeyClass(IntWritable.class);
     job.setOutputValueClass(IntWritable.class);
-    FileInputFormat.addInputPath(job, new Path(args[0]));
-    FileOutputFormat.setOutputPath(job, new Path(args[1]));
+    FileInputFormat.addInputPath(job, new Path(otherArgs[0]));
+    FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));
     boolean result = job.waitForCompletion(true);
 
     // Wait for JOB 1 -- get middle value to check for Median