Revert "MAPREDUCE-5911. Terasort TeraOutputFormat does not check for output directory existance. Contributed by Bruno P. Kinoshita."

This reverts commit 71e05b190050aac2fa8ed6d7d6ad023a275c0f1e.

hadoop-mapreduce-project/CHANGES.txt

@@ -204,9 +204,6 @@ Release 2.6.0 - UNRELEASED
     MAPREDUCE-5542. Killing a job just as it finishes can generate an NPE in
     client (Rohith via jlowe)
 
-    MAPREDUCE-5911. Terasort TeraOutputFormat does not check for output
-    directory existance (Bruno P. Kinoshita via ivanmi)
-
 Release 2.5.1 - 2014-09-05
 
   INCOMPATIBLE CHANGES

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

@@ -24,7 +24,6 @@ import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.io.Text;
-import org.apache.hadoop.mapred.FileAlreadyExistsException;
 import org.apache.hadoop.mapred.InvalidJobConfException;
 import org.apache.hadoop.mapreduce.JobContext;
 import org.apache.hadoop.mapreduce.OutputCommitter;
@@ -91,11 +90,6 @@ public class TeraOutputFormat extends FileOutputFormat<Text,Text> {
     // get delegation token for outDir's file system
     TokenCache.obtainTokensForNamenodes(job.getCredentials(),
         new Path[] { outDir }, job.getConfiguration());
-
-    if (outDir.getFileSystem(job.getConfiguration()).exists(outDir)) {
-      throw new FileAlreadyExistsException("Output directory " + outDir + 
-                                           " already exists");
-    }
   }
 
   public RecordWriter<Text,Text> getRecordWriter(TaskAttemptContext job