java - 提交 MapReduce 作业时出错

Question

我有 2 个包含书籍数据详细信息的 csv 文件。我已经编写了java代码并制作了jar文件。

在执行 jar 文件时出现以下错误。如果您需要，我可以共享完整的数据集和代码。请求帮助我查询。`

user@ubuntu:~$ hadoop jar /home/user/Desktop/project1_usecase3.jar /Input/BX-Book-Ratings.csv /Output
18/03/23 02:28:23 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
18/03/23 02:28:25 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
18/03/23 02:28:25 WARN mapreduce.JobSubmitter: Hadoop command-line option parsing not performed. Implement the Tool interface and execute your application with ToolRunner to remedy this.
18/03/23 02:28:26 INFO mapreduce.JobSubmitter: Cleaning up the staging area /tmp/hadoop-yarn/staging/user/.staging/job_1521796431998_0005
Exception in thread "main" org.apache.hadoop.mapreduce.lib.input.InvalidInputException: Input path does not exist: hdfs://localhost:9000/input/BX-Book-Ratings.csv
    at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.singleThreadedListStatus(FileInputFormat.java:321)
    at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.listStatus(FileInputFormat.java:264)
    at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.getSplits(FileInputFormat.java:385)
    at org.apache.hadoop.mapreduce.lib.input.DelegatingInputFormat.getSplits(DelegatingInputFormat.java:115)
    at org.apache.hadoop.mapreduce.JobSubmitter.writeNewSplits(JobSubmitter.java:597)
    at org.apache.hadoop.mapreduce.JobSubmitter.writeSplits(JobSubmitter.java:614)
    at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:492)
    at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1296)
    at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1293)
    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:1628)
    at org.apache.hadoop.mapreduce.Job.submit(Job.java:1293)
    at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1314)
    at com.edunextgen.maven.project1.NumBook.main(NumBook.java:106)
    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.run(RunJar.java:221)
    at org.apache.hadoop.util.RunJar.main(RunJar.java:136)`

Answer 1

请记住，/Input/BX-Book-Ratings.csv 需要存在于 HDFS 而不是您的本地机器上。如果你执行 hdfs dfs -ls/input，你看到文件了吗？

如果没有，就做

hdfs dfs -copyFromLocal <csv-file-local-location> /Input/BX-Book-Ratings.csv