我是新的hadoop和安装hadoop 2.2.0后，我试图遵循示例http://www.srccodes.com/p/article/45/run-hadoop-wordcount-mapreduce-example-windows尝试一个简单的映射减少工作。
然而，每当我尝试在我创建的txt文件上执行map reduce作业时，我总是收到此消息
的失败。c:hadoop>binyarn jar share/hadoop/mapreduce/hadoop-mapreduce-examples-2.2.0.ja
r wordcount /input output
14/03/26 14:20:48 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0
:8032
14/03/26 14:20:50 INFO input.FileInputFormat: Total input paths to process : 1
14/03/26 14:20:51 INFO mapreduce.JobSubmitter: number of splits:1
14/03/26 14:20:51 INFO Configuration.deprecation: user.name is deprecated. Inste
ad, use mapreduce.job.user.name
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.jar is deprecated. Inst
ead, use mapreduce.job.jar
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.output.value.class is d
eprecated. Instead, use mapreduce.job.output.value.class
14/03/26 14:20:51 INFO Configuration.deprecation: mapreduce.combine.class is dep
recated. Instead, use mapreduce.job.combine.class
14/03/26 14:20:51 INFO Configuration.deprecation: mapreduce.map.class is depreca
ted. Instead, use mapreduce.job.map.class
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.job.name is deprecated.
Instead, use mapreduce.job.name
14/03/26 14:20:51 INFO Configuration.deprecation: mapreduce.reduce.class is depr
ecated. Instead, use mapreduce.job.reduce.class
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.input.dir is deprecated
. Instead, use mapreduce.input.fileinputformat.inputdir
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.output.dir is deprecate
d. Instead, use mapreduce.output.fileoutputformat.outputdir
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.map.tasks is deprecated
. Instead, use mapreduce.job.maps
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.output.key.class is dep
recated. Instead, use mapreduce.job.output.key.class
14/03/26 14:20:51 INFO Configuration.deprecation: mapred.working.dir is deprecat
ed. Instead, use mapreduce.job.working.dir
14/03/26 14:20:51 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_13
95833928952_0004
14/03/26 14:20:52 INFO impl.YarnClientImpl: Submitted application application_13
95833928952_0004 to ResourceManager at /0.0.0.0:8032
14/03/26 14:20:52 INFO mapreduce.Job: The url to track the job: http://GoncaloPe
reira:8088/proxy/application_1395833928952_0004/
14/03/26 14:20:52 INFO mapreduce.Job: Running job: job_1395833928952_0004
14/03/26 14:21:08 INFO mapreduce.Job: Job job_1395833928952_0004 running in uber
mode : false
14/03/26 14:21:08 INFO mapreduce.Job: map 0% reduce 0%
14/03/26 14:21:20 INFO mapreduce.Job: Task Id : attempt_1395833928952_0004_m_000
000_0, Status : FAILED
Error: java.lang.ClassCastException: org.apache.hadoop.mapreduce.lib.input.FileS
plit cannot be cast to org.apache.hadoop.mapred.InputSplit
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:402)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:162)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInforma
tion.java:1491)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:157)
14/03/26 14:21:33 INFO mapreduce.Job: Task Id : attempt_1395833928952_0004_m_000
000_1, Status : FAILED
Error: java.lang.ClassCastException: org.apache.hadoop.mapreduce.lib.input.FileS
plit cannot be cast to org.apache.hadoop.mapred.InputSplit
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:402)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:162)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInforma
tion.java:1491)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:157)
14/03/26 14:21:48 INFO mapreduce.Job: Task Id : attempt_1395833928952_0004_m_000
000_2, Status : FAILED
Error: java.lang.ClassCastException: org.apache.hadoop.mapreduce.lib.input.FileS
plit cannot be cast to org.apache.hadoop.mapred.InputSplit
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:402)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:162)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInforma
tion.java:1491)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:157)
14/03/26 14:22:04 INFO mapreduce.Job: map 100% reduce 100%
14/03/26 14:22:10 INFO mapreduce.Job: Job job_1395833928952_0004 failed with sta
te FAILED due to: Task failed task_1395833928952_0004_m_000000
Job failed as tasks failed. failedMaps:1 failedReduces:0
14/03/26 14:22:10 INFO mapreduce.Job: Counters: 6
Job Counters
Failed map tasks=4
Launched map tasks=4
Other local map tasks=3
Data-local map tasks=1
Total time spent by all maps in occupied slots (ms)=48786
Total time spent by all reduces in occupied slots (ms)=0
因为我跟着一切没有问题一步一步我不知道为什么这可能是，有人知道吗?
编辑:尝试采用2.3.0相同的问题发生与给出的示例jar，下面的代码我尝试编译，不知道问题是什么
import java.io.IOException;
import java.util.*;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.io.*;
import org.apache.hadoop.mapreduce.*;
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;
public class teste {
public static class Map extends Mapper<LongWritable, Text, Text, IntWritable> {
private final static IntWritable one = new IntWritable(1);
private Text word = new Text();
public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
String line = value.toString();
StringTokenizer tokenizer = new StringTokenizer(line);
while (tokenizer.hasMoreTokens()) {
word.set(tokenizer.nextToken());
context.write(word, one);
}
}
}
public static class Reduce extends Reducer<Text, IntWritable, Text, IntWritable> {
public void reduce(Text key, Iterable<IntWritable> values, Context context)
throws IOException, InterruptedException {
int sum = 0;
for (IntWritable val : values) {
sum += val.get();
}
context.write(key, new IntWritable(sum));
}
}
public static void main(String[] args) throws Exception {
Configuration conf = new Configuration();
Job job = new Job(conf, "wordcount");
job.setJarByClass(teste.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(IntWritable.class);
job.setMapperClass(Map.class);
job.setReducerClass(Reduce.class);
job.setInputFormatClass(TextInputFormat.class);
job.setOutputFormatClass(TextOutputFormat.class);
FileInputFormat.addInputPath(job, new Path(args[0]));
FileOutputFormat.setOutputPath(job, new Path(args[1]));
job.waitForCompletion(true);
}
}
我有同样的问题(java.lang.ClassCastException)，并能够通过运行具有管理员权限的Hadoop来解决它。问题似乎是创建符号链接，默认情况下，非管理员Windows用户是不可能的。以管理员身份打开控制台，然后按照链接中的示例所述进行操作。
您提供的链接的输入参数为input NOT/input…试试这个语法…
C:hadoop>binyarn jar share/hadoop/mapreduce/hadoop-mapreduce-examples-2.2.0.jar wordcount input output