hadoop hdfs文件系统文件以存在 解决办法

佘小宝的爹

hadoop@salve:~/programfile/hadoop$ bin/hadoop jar hadoop-examples-*.jar wordcount /input /output　　
14/05/16 08:50:00 INFO mapred.JobClient: Cleaning up the staging area hdfs://localhost:9000/tmp/hadoop-hadoop/mapred/staging/hadoop/.staging/job_201405160835_0004
　　
14/05/16 08:50:00 ERROR security.UserGroupInformation: PriviledgedActionException as:hadoop cause:org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory /output already exists
　　
org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory /output already exists
　　at org.apache.hadoop.mapreduce.lib.output.FileOutputFormat.checkOutputSpecs(FileOutputFormat.java:137)
　　at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:949)
　　at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:912)
　　at java.security.AccessController.doPrivileged(Native Method)
　　at javax.security.auth.Subject.doAs(Subject.java:415)
　　at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1136)
　　at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:912)
　　at org.apache.hadoop.mapreduce.Job.submit(Job.java:500)
　　at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:530)
　　at org.apache.hadoop.examples.WordCount.main(WordCount.java:67)
　　at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
　　at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
　　at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
　　at java.lang.reflect.Method.invoke(Method.java:606)
　　at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:68)
　　at org.apache.hadoop.util.ProgramDriver.driver(ProgramDriver.java:139)
　　at org.apache.hadoop.examples.ExampleDriver.main(ExampleDriver.java:64)
　　at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
　　at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
　　at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
　　at java.lang.reflect.Method.invoke(Method.java:606)
　　
at org.apache.hadoop.util.RunJar.main(RunJar.java:156)