Java 将数据从mongoDB复制到hdfs时发生hadoop jar错误
我正在尝试使用HadoopMongodb连接器将集合从mongodb复制到hadoop 使用以下代码: 包装hdfsJava 将数据从mongoDB复制到hdfs时发生hadoop jar错误,java,mongodb,hadoop,jar,Java,Mongodb,Hadoop,Jar,我正在尝试使用HadoopMongodb连接器将集合从mongodb复制到hadoop 使用以下代码: 包装hdfs import java.io.*; import org.apache.commons.logging.*; import org.apache.hadoop.conf.*; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.*; import org.apache.hadoop.mapreduce.lib
import java.io.*;
import org.apache.commons.logging.*;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.*;
import org.apache.hadoop.mapreduce.lib.output.*;
import org.apache.hadoop.mapreduce.*;
import org.bson.*;
import com.mongodb.hadoop.*;
import com.mongodb.hadoop.util.*;
public class ImportWeblogsFromMongo {
private static final Log log = LogFactory.getLog(ImportWeblogsFromMongo.class);
public static class ReadWeblogsFromMongo extends Mapper<Object, BSONObject, Text, Text> {
public void map(Object key, BSONObject value, Context context) throws IOException, InterruptedException {
System.out.println("Key: " + key);
System.out.println("Value: " + value);
String md5 = value.get("md5").toString();
String url = value.get("url").toString();
String date = value.get("date").toString();
String time = value.get("time").toString();
String ip = value.get("ip").toString();
String output = "\t" + url + "\t" + date + "\t" + time + "\t" + ip;
context.write(new Text(md5), new Text(output));
}
}
public static void main(String[] args) throws Exception {
final Configuration conf = new Configuration();
MongoConfigUtil.setInputURI(conf,"mongodb://localhost:27017/clusterdb.fish");
MongoConfigUtil.setCreateInputSplits(conf, false);
System.out.println("Configuration: " + conf);
@SuppressWarnings("deprecation")
final Job job = new Job(conf, "Mongo Import");
Path out = new Path("/home/mongo_import");
FileOutputFormat.setOutputPath(job, out);
job.setJarByClass(ImportWeblogsFromMongo.class);
job.setMapperClass(ReadWeblogsFromMongo.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(Text.class);
job.setInputFormatClass(MongoInputFormat.class);
job.setOutputFormatClass(TextOutputFormat.class);
job.setNumReduceTasks(0);
System.exit(job.waitForCompletion(true) ? 0 : 1);
}
}
NB:clustedb是数据库名称及其集合
而hdfs.importwewBlogsFrommongo是package.class
请提供任何建议我没有以这种方式解决问题,但我使用
Mongodump
找到了解决方案。通过将文件复制到Hdfs
,下面的行可以帮助某人完成工作
mongodump --db clusterdb --collection CollectionName
bsondump file.bson > file.json
hadoop dfs -copyFromLocal /path/to/file/fish.json mongo
你试过hadoop jar/home/yass/importmongo.jar-libjars hadoop\u MONGODB\u jar hdfs.importwewBlogsFrommongo?是的,我在线程“main”java.lang.ClassNotFoundException:-libjarssory中得到了一个异常:-libjar,我的意思是
hadoop jar/home/yass/importmongo.jar hdfs.ImportWeblogsFromMongo-libjars hadoop\u MONGODB\u jar
。您可以查看或以了解使用-libjars的正确语法。
mongodump --db clusterdb --collection CollectionName
bsondump file.bson > file.json
hadoop dfs -copyFromLocal /path/to/file/fish.json mongo