Java 为什么我的程序会收到一个；“未设置作业jar文件”；错误？

下面是我的代码，很明显，我已经用

job.setJarByClass（

KnnDriver.class）`按类设置了jar

有人能帮我调试一下吗

import java.net.URI;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

public class KnnDriver extends Configured implements Tool{
    /*
     *  args = N, test.csv, train.csv, outputpath
     */
    public static void main(String[] args) throws Exception {
        int res = ToolRunner.run(new Configuration(), new KnnDriver(), args);
        System.exit(res);
    }

    @Override
    public int run(String[] args) throws Exception {
        Configuration conf = getConf();
        conf.set("N", args[0]);

        Job job = Job.getInstance(conf, "K-Nearest-Neighbor mapreduce");        
        job.setJarByClass(KnnDriver.class);

        job.addCacheFile(new URI(args[1]));

        if (args.length != 4) {
            System.err.println("Number of parameter is not correct!");
            System.exit(2);
        }

        job.setMapperClass(KnnMapper.class);
        job.setReducerClass(KnnReducer.class);

        // TODO: specify output types
        job.setOutputKeyClass(LongWritable.class);
        job.setMapOutputValueClass(DistClassPair.class);
        job.setOutputValueClass(Text.class);

        job.setInputFormatClass(TextInputFormat.class);
        job.setOutputFormatClass(TextOutputFormat.class);

        // TODO: specify input and output DIRECTORIES (not files)
        FileInputFormat.setInputPaths(job, new Path(args[2]));

        Path outputPath = new Path(args[3]);
        FileSystem.get(conf).delete(outputPath, true);
        FileOutputFormat.setOutputPath(job, outputPath);

        return(job.waitForCompletion(true) ? 0 : -1);
    }

}

此外，这里是堆栈信息

2016-02-25 04:00:31,240 WARN  [main] util.NativeCodeLoader (NativeCodeLoader.java:<clinit>(62)) - Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
2016-02-25 04:00:31,449 INFO  [main] Configuration.deprecation (Configuration.java:warnOnceIfDeprecated(1173)) - session.id is deprecated. Instead, use dfs.metrics.session-id
2016-02-25 04:00:31,450 INFO  [main] jvm.JvmMetrics (JvmMetrics.java:init(76)) - Initializing JVM Metrics with processName=JobTracker, sessionId=
2016-02-25 04:00:31,603 WARN  [main] mapreduce.JobResourceUploader (JobResourceUploader.java:uploadFiles(171)) - No job jar file set.  User classes may not be found. See Job or Job#setJar(String).
2016-02-25 04:00:31,650 INFO  [main] input.FileInputFormat (FileInputFormat.java:listStatus(283)) - Total input paths to process : 1
2016-02-25 04:00:31,697 INFO  [main] mapreduce.JobSubmitter (JobSubmitter.java:submitJobInternal(198)) - number of splits:1
2016-02-25 04:00:31,778 INFO  [main] mapreduce.JobSubmitter (JobSubmitter.java:printTokens(287)) - Submitting tokens for job: job_local225811898_0001
2016-02-25 04:00:32,014 INFO  [main] mapred.LocalDistributedCacheManager (LocalDistributedCacheManager.java:symlink(201)) - Creating symlink: /tmp/hadoop-xupengtong/mapred/local/1456390831864/test.csv <- /Volumes/TONY/Big_Data/KnnMapReduce/test.csv
2016-02-25 04:00:32,019 INFO  [main] mapred.LocalDistributedCacheManager (LocalDistributedCacheManager.java:setup(165)) - Localized file:/Volumes/TONY/Big_Data/KnnMapReduce/data/test.csv as file:/tmp/hadoop-xupengtong/mapred/local/1456390831864/test.csv
2016-02-25 04:00:32,058 INFO  [main] mapreduce.Job (Job.java:submit(1294)) - The url to track the job: http://localhost:8080/
2016-02-25 04:00:32,059 INFO  [main] mapreduce.Job (Job.java:monitorAndPrintJob(1339)) - Running job: job_local225811898_0001
2016-02-25 04:00:32,060 INFO  [Thread-21] mapred.LocalJobRunner (LocalJobRunner.java:createOutputCommitter(471)) - OutputCommitter set in config null
2016-02-25 04:00:32,064 INFO  [Thread-21] output.FileOutputCommitter (FileOutputCommitter.java:<init>(100)) - File Output Committer Algorithm version is 1
2016-02-25 04:00:32,066 INFO  [Thread-21] mapred.LocalJobRunner (LocalJobRunner.java:createOutputCommitter(489)) - OutputCommitter is org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter
2016-02-25 04:00:32,094 INFO  [Thread-21] mapred.LocalJobRunner (LocalJobRunner.java:runTasks(448)) - Waiting for map tasks
2016-02-25 04:00:32,095 INFO  [LocalJobRunner Map Task Executor #0] mapred.LocalJobRunner (LocalJobRunner.java:run(224)) - Starting task: attempt_local225811898_0001_m_000000_0
2016-02-25 04:00:32,115 INFO  [LocalJobRunner Map Task Executor #0] output.FileOutputCommitter (FileOutputCommitter.java:<init>(100)) - File Output Committer Algorithm version is 1
2016-02-25 04:00:32,121 INFO  [LocalJobRunner Map Task Executor #0] util.ProcfsBasedProcessTree (ProcfsBasedProcessTree.java:isAvailable(192)) - ProcfsBasedProcessTree currently is supported only on Linux.
2016-02-25 04:00:32,121 INFO  [LocalJobRunner Map Task Executor #0] mapred.Task (Task.java:initialize(612)) -  Using ResourceCalculatorProcessTree : null
2016-02-25 04:00:32,124 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:runNewMapper(756)) - Processing split: file:/Volumes/TONY/Big_Data/KnnMapReduce/data/train.csv:0+4447014
2016-02-25 04:00:32,229 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:setEquator(1205)) - (EQUATOR) 0 kvi 26214396(104857584)
2016-02-25 04:00:32,229 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:init(998)) - mapreduce.task.io.sort.mb: 100
2016-02-25 04:00:32,229 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:init(999)) - soft limit at 83886080
2016-02-25 04:00:32,229 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:init(1000)) - bufstart = 0; bufvoid = 104857600
2016-02-25 04:00:32,229 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:init(1001)) - kvstart = 26214396; length = 6553600
2016-02-25 04:00:32,233 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:createSortingCollector(403)) - Map output collector class = org.apache.hadoop.mapred.MapTask$MapOutputBuffer
2016-02-25 04:00:32,352 INFO  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:flush(1460)) - Starting flush of map output
2016-02-25 04:00:32,360 INFO  [Thread-21] mapred.LocalJobRunner (LocalJobRunner.java:runTasks(456)) - map task executor complete.
2016-02-25 04:00:32,361 WARN  [Thread-21] mapred.LocalJobRunner (LocalJobRunner.java:run(560)) - job_local225811898_0001
java.lang.Exception: java.lang.NullPointerException
    at org.apache.hadoop.mapred.LocalJobRunner$Job.runTasks(LocalJobRunner.java:462)
    at org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:522)
Caused by: java.lang.NullPointerException
    at java.util.StringTokenizer.<init>(StringTokenizer.java:199)
    at java.util.StringTokenizer.<init>(StringTokenizer.java:221)
    at KnnMapper.setup(KnnMapper.java:67)
    at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:143)
    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
    at org.apache.hadoop.mapred.LocalJobRunner$Job$MapTaskRunnable.run(LocalJobRunner.java:243)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
2016-02-25 04:00:33,061 INFO  [main] mapreduce.Job (Job.java:monitorAndPrintJob(1360)) - Job job_local225811898_0001 running in uber mode : false
2016-02-25 04:00:33,062 INFO  [main] mapreduce.Job (Job.java:monitorAndPrintJob(1367)) -  map 0% reduce 0%
2016-02-25 04:00:33,066 INFO  [main] mapreduce.Job (Job.java:monitorAndPrintJob(1380)) - Job job_local225811898_0001 failed with state FAILED due to: NA
2016-02-25 04:00:33,070 INFO  [main] mapreduce.Job (Job.java:monitorAndPrintJob(1385)) - Counters: 0

2016-02-25 04:00:31240警告[main]util.NativeCodeLoader（NativeCodeLoader.java:（62））-无法为您的平台加载本机hadoop库。。。在适用的情况下使用内置java类
2016-02-25 04:00:31449 INFO[main]Configuration.deprecated（Configuration.java:warnOnceIfDeprecated（1173））-session.id已被弃用。而是使用dfs.metrics.session-id
2016-02-25 04:00:31450信息[main]jvm.JvmMetrics（JvmMetrics.java:init（76））-使用processName=JobTracker，sessionId初始化jvm度量=
2016-02-25 04:00:31603警告[main]mapreduce.JobResourceUploader（JobResourceUploader.java:uploadFiles（171））-未设置作业jar文件。可能找不到用户类。请参阅作业或作业#setJar（字符串）。
2016-02-25 04:00:31650 INFO[main]input.FileInputFormat（FileInputFormat.java:listStatus（283））-处理的总输入路径：1
2016-02-25 04:00:31697信息[main]mapreduce.jobsmitter（jobsmitter.java:submitJobInternal（198））-拆分数量：1
2016-02-25 04:00:31778信息[main]mapreduce.jobsmitter（jobsmitter.java:printTokens（287））-提交作业令牌：job\u local225811898\u 0001
2016-02-25 04:00:32014 INFO[main]mapred.LocalDistributedCacheManager（LocalDistributedCacheManager.java:symlink（201））-创建符号链接：/tmp/hadoop xupengtong/mapred/local/1456390831864/test.csv确保在map和reduce中使用的所有变量都已初始化。
我也有同样的问题
你能发布你得到的堆栈跟踪错误吗？你在这篇文章的标题中看到你报告的错误在哪里？我所能看到的只是KnnMapper类引发的NullPointerException。我认为您的错误在这里
KnnMapper.setup（KnnMapper.java:67）
@mikea这是跟踪中的第一个警告，但我也同意您的看法。但是，尽管程序与您指出的异常基本上是错误的，为什么会有关于此异常的警告“没有作业jar文件集”？@ArnonZilca为什么你认为这不能提供答案？它清楚地表明OP需要什么来解决他的问题。