Hadoop MapReduceエラー No such file or directory

Hadoopを勉強中でHadoopストリーミングをテストするためrubyで書いたmapperとreducerが正しく動作するかコマンドラインからMapReduceを実行してみました。
しかし、mapper.rbがないと下記のようにエラーが表示されて正しくジョブが実行されません。

dir/usercache/Kuma/appcache/application_1469093819516_0005/container_1469093819516_0005_01_000002/./mapper.rb": error=2, No such file or directory

実行したコマンド

hadoop jar hadoop-streaming-2.7.2.jar -files mapper.rb,reducer.rb -mapper mapper.rb -reducer reducer.rb -input test.json -output test

mapper.rb、reducer.rbともにコマンドを実行したカレントディレクトリに存在するファイルです。Hadoop初心者でどこに問題があるかわかりません。
テスト用のMapReduceであるwordcountでは正しく実行され、エラーなく結果が出力されていたのでHadoop本体の設定は問題無いと思います。
アドバイスよろしくお願いします。

環境
Mac EI Capitan
Hadoop 2.7.2（擬似分散モード）

jobのエラー全文です。

16/07/21 19:22:04 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
packageJobJar: [/var/folders/l_/21nh6rmn6f3fn3vd55kh0b5h0000gn/T/hadoop-unjar8708804571112102348/] [] /var/folders/l_/21nh6rmn6f3fn3vd55kh0b5h0000gn/T/streamjob5933629893966751936.jar tmpDir=null
16/07/21 19:22:05 INFO client.RMProxy: Connecting to ResourceManager at localhost/127.0.0.1:8032
16/07/21 19:22:05 INFO client.RMProxy: Connecting to ResourceManager at localhost/127.0.0.1:8032
16/07/21 19:22:06 INFO mapred.FileInputFormat: Total input paths to process : 1
16/07/21 19:22:06 INFO mapreduce.JobSubmitter: number of splits:2
16/07/21 19:22:06 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1469093819516_0005
16/07/21 19:22:06 INFO impl.YarnClientImpl: Submitted application application_1469093819516_0005
16/07/21 19:22:06 INFO mapreduce.Job: The url to track the job: http://hatanokaoruakira-no-MacBook-Air.local:8088/proxy/application_1469093819516_0005/
16/07/21 19:22:06 INFO mapreduce.Job: Running job: job_1469093819516_0005
16/07/21 19:22:13 INFO mapreduce.Job: Job job_1469093819516_0005 running in uber mode : false
16/07/21 19:22:13 INFO mapreduce.Job:  map 0% reduce 0%
16/07/21 19:22:18 INFO mapreduce.Job: Task Id : attempt_1469093819516_0005_m_000000_0, Status : FAILED
Error: java.lang.RuntimeException: Error in configuring object
    at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:112)
    at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:78)
    at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:136)
    at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:449)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:343)
    at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:422)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
    at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:109)
    ... 9 more
Caused by: java.lang.RuntimeException: Error in configuring object
    at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:112)
    at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:78)
    at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:136)
    at org.apache.hadoop.mapred.MapRunner.configure(MapRunner.java:38)
    ... 14 more
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:109)
    ... 17 more
Caused by: java.lang.RuntimeException: configuration exception
    at org.apache.hadoop.streaming.PipeMapRed.configure(PipeMapRed.java:222)
    at org.apache.hadoop.streaming.PipeMapper.configure(PipeMapper.java:66)
    ... 22 more
Caused by: java.io.IOException: Cannot run program "/private/tmp/hadoop-Kuma/nm-local-dir/usercache/Kuma/appcache/application_1469093819516_0005/container_1469093819516_0005_01_000002/./mapper.rb": error=2, No such file or directory
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
    at org.apache.hadoop.streaming.PipeMapRed.configure(PipeMapRed.java:209)
    ... 23 more
Caused by: java.io.IOException: error=2, No such file or directory
    at java.lang.UNIXProcess.forkAndExec(Native Method)
    at java.lang.UNIXProcess.<init>(UNIXProcess.java:248)
    at java.lang.ProcessImpl.start(ProcessImpl.java:134)
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
    ... 24 more