Failed query execution: java.lang.NoClassDefFoundError: com/mongodb/util/JSON

[Mariana Gavrilescu]

I have installed the mongo-hadoop connector specifying the hadoop version I use, at the building time

./gradlew jar -Phadoop_version=2.2

Using Hue I have copied the jars on HDFS:

mongo-hadoop-core-1.4.0-SNAPSHOT.jar

mongo-hadoop-hive-1.4.0-SNAPSHOT.jar

mongo-hadoop.jar

In the Hive editor I added the already enumerated jar and I tried to ran the following query:

DROP TABLE IF EXISTS users;

CREATE TABLE users

( 

  id INT,

  name STRING,

  age INT

  

)

STORED BY 'com.mongodb.hadoop.hive.MongoStorageHandler'

WITH SERDEPROPERTIES('mongo.columns.mapping'='{"id":"_id","name":"name","age":"age"}')

TBLPROPERTIES('mongo.uri'='mongodb://localhost:27017/test.users');

The "users" collection exists in MongoDB.

I get the following exception:

14/07/10 11:42:55 ERROR exec.DDLTask: java.lang.NoClassDefFoundError: com/mongodb/util/JSON
	at com.mongodb.hadoop.hive.BSONSerDe.initialize(BSONSerDe.java:107)
	at org.apache.hadoop.hive.metastore.MetaStoreUtils.getDeserializer(MetaStoreUtils.java:170)
	at org.apache.hadoop.hive.ql.metadata.Table.getDeserializerFromMetaStore(Table.java:272)
	at org.apache.hadoop.hive.ql.metadata.Table.getDeserializer(Table.java:265)
	at org.apache.hadoop.hive.ql.metadata.Table.getCols(Table.java:597)
	at org.apache.hadoop.hive.ql.metadata.Hive.createTable(Hive.java:578)
	at org.apache.hadoop.hive.ql.exec.DDLTask.createTable(DDLTask.java:3697)
	at org.apache.hadoop.hive.ql.exec.DDLTask.execute(DDLTask.java:253)
	at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:151)
	at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:65)
	at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:1485)
	at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:1263)
	at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1091)
	at org.apache.hadoop.hive.ql.Driver.run(Driver.java:931)
	at org.apache.hadoop.hive.ql.Driver.run(Driver.java:926)
	at org.apache.hive.service.cli.operation.SQLOperation.runInternal(SQLOperation.java:144)
	at org.apache.hive.service.cli.operation.SQLOperation.access$100(SQLOperation.java:64)
	at org.apache.hive.service.cli.operation.SQLOperation$1.run(SQLOperation.java:177)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: com.mongodb.util.JSON
	at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
	... 23 more

[Will Berkeley]

Hi. The error indicates that the com.mongodb.util.JSON class could not be loaded. Have you copied the mongo-java-driver jar so it's available on Hadoop as well? See the installation instructions for mongo-hadoop.

-Will

[hei yingzi]

I use mongodb in hive, and add jar to calling mongo-java-driver and sees the same execution

在 2014年7月12日星期六 UTC+8上午12:48:54，Will Berkeley写道：

[Wan Bachtiar]

I use mongodb in hive, and add jar to calling mongo-java-driver and sees the same execution

Hi YingZi,

Although you may see a similar error, it may be entirely different reason causing it.

Please open a new discussion thread along with the following relevant information:

• MongoDB version
• mongo-hadoop connector version
• Apache Hive version
• The jars and their respective versions
• The commands that you executed
• Stack trace or error messages

Regards,
Wan.

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