我的作业配置如下，我正在尝试对我的 hadoop 作业进行简单的两步链接，

public int run(String[] args) throws Exception {
        Configuration conf = getConf();
        if (args.length != 2) {
            System.err.println("Usage: moviecount3 <in> <out>");
            System.exit(2);
        }

        ConfigurationUtil.dumpConfigurations(conf, System.out);

        LOG.info("input: " + args[0] + " output: " + args[1]);

        Job job = new Job(conf, "movie count2");
        job.setJarByClass(MovieCount3.class);
        job.setMapperClass(MovieTokenizerMapper3.class);
        job.setReducerClass(MovieActorReducer3.class);

        job.setMapOutputKeyClass(Text.class);
        job.setMapOutputValueClass(IntWritable.class);

        job.setOutputKeyClass(IntWritable.class);
        job.setOutputValueClass(Text.class);

        FileInputFormat.addInputPath(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));

        boolean result = job.waitForCompletion(true);

        //Job 2
        Job job2 = new Job(conf, "movie count22");
        if(job.isSuccessful()){
            job2.setJarByClass(MovieCount3.class);
            job2.setMapperClass(MovieActorCombiner3.class);
            //job2.setReducerClass(MovieActorReducer3.class);

            job2.setMapOutputKeyClass(Text.class);
            job2.setMapOutputValueClass(IntWritable.class);

            job2.setOutputKeyClass(IntWritable.class);
            job2.setOutputValueClass(Text.class);

            FileInputFormat.addInputPath(job, new Path("/user/test/output/part-r-00000"));
            FileOutputFormat.setOutputPath(job, new Path("/user/test/output2"));
        }
        boolean result2 = job2.waitForCompletion(true);
        return (result2) ? 0 : 1;
    }

运行此配置时出现以下异常，

12/11/22 14:21:30 INFO mapred.JobClient: Cleaning up the staging area hdfs://localhost:9000/media/LinuxDrive/hdfs-test/mapred/staging/test/.staging/job_201211221353_0010
12/11/22 14:21:30 ERROR security.UserGroupInformation: PriviledgedActionException as:test
cause:org.apache.hadoop.mapred.InvalidJobConfException: Output directory not set.
org.apache.hadoop.mapred.InvalidJobConfException: Output directory not set.
    at org.apache.hadoop.mapreduce.lib.output.FileOutputFormat.checkOutputSpecs(FileOutputFormat.java:128)
    at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:887)
    at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:850)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:396)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1121)
    at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:850)
    at org.apache.hadoop.mapreduce.Job.submit(Job.java:500)
    at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:530)
    at ucsc.hadoop.mapreduce.movie.MovieCount3.run(MovieCount3.java:77)
    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79)
    at ucsc.hadoop.mapreduce.movie.MovieCount3.main(MovieCount3.java:84)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:68)
    at org.apache.hadoop.util.ProgramDriver.driver(ProgramDriver.java:139)
    at ucsc.hadoop.mapreduce.ExampleDriver.main(ExampleDriver.java:101)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.apache.hadoop.util.RunJar.main(RunJar.java:156)

谢谢!

最佳答案

问题是，您没有为第二个作业设置输出目录。您再次设置第一个作业的输出:

错误:

FileInputFormat.addInputPath(job, new Path("/user/test/output/part-r-00000"));
FileOutputFormat.setOutputPath(job, new Path("/user/test/output2"));

右:

FileInputFormat.addInputPath(job2, new Path("/user/test/output/part-r-00000"));
FileOutputFormat.setOutputPath(job2, new Path("/user/test/output2"));

这应该可以解决您的问题。

关于Hadoop异常-清理暂存区/staging/test/.staging/job_201211221353_0010，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/13520814/