please help, I'm stuck.
Here is my code to run job.
hadoop jar mrjob.jar ru.package.Main -files hdfs://0.0.0.0:8020/MyCatalog/jars/metadata.csv -libjars hdfs://0.0.0.0:8020/MyCatalog/jars/opencsv.jar,hdfs://0.0.0.0:8020/MyCatalog/jars/gson.jar,hdfs://0.0.0.0:8020/MyCatalog/jars/my-utils.jar /MyCatalog/http_requests.seq-r-00000 /MyCatalog/output/result_file
I do get these WARNs:
12/10/26 18:35:50 WARN util.GenericOptionsParser: The libjars file hdfs://0.0.0.0:8020/MyCatalog/jars/opencsv.jar is not on the local filesystem. Ignoring.
12/10/26 18:35:50 WARN util.GenericOptionsParser: The libjars file hdfs://0.0.0.0:8020/MyCatalog/jars/gson.jar is not on the local filesystem. Ignoring.
12/10/26 18:35:50 WARN util.GenericOptionsParser: The libjars file hdfs://0.0.0.0:8020/MyCatalog/jars/my-utils.jar is not on the local filesystem. Ignoring.
Then: Exception in thread "main" java.lang.NoClassDefFoundError:
on line in Main class where I try to instantiate class from jar named my-utils.jar
- All these jars are in hfds (I see them through file browser)
- my-utils.jar does contain class which is a reason for NoClassDefFoundError
What do I do wrong?
UPD:
I'm inspecting sourcecode of GenericOptionsParser:
/**
* If libjars are set in the conf, parse the libjars.
* @param conf
* @return libjar urls
* @throws IOException
*/
public static URL[] getLibJars(Configuration conf) throws IOException {
String jars = conf.get("tmpjars");
if(jars==null) {
return null;
}
String[] files = jars.split(",");
List<URL> cp = new ArrayList<URL>();
for (String file : files) {
Path tmp = new Path(file);
if (tmp.getFileSystem(conf).equals(FileSystem.getLocal(conf))) {
cp.add(FileSystem.getLocal(conf).pathToFile(tmp).toURI().toURL());
} else {
LOG.warn("The libjars file " + tmp + " is not on the local " +
"filesystem. Ignoring.");
}
}
return cp.toArray(new URL[0]);
}
So:
1. no spaces between comma
2. still don't get it… I've tried to point to: local file system, hdfs file system, result is the same. Seems like class is not added…
Best Answer
Problem is solved. correct invocation is:
where
is hdfs path,
is local fs path The problem was in job jar. Previously I did try to run job using simple jar with only three classes: Mapper, Reducer, Main class. Now I did provide other one generated by maven (it generates two of them) The second job jar contains all dependency libs. in side it. Structure looks like: my-job.jar
-lib
--aopalliance-1.0.jar asm-3.2.jar avro-1.5.4.jar ... commons-beanutils-1.7.0.jar commons-beanutils-core-1.8.0.jar ... zookeeper-3.4.3-cdh4.0.0.jar
There are 76 jars inside lib folder.
It works but I don't understand why.