spark scala warning : do they need to be resolved? - scala

Question

I get below screen when I run Scala (Using Scala version 2.10.5). I am using it along with Spark version 1.6.1. The book that I am learning from has a screenshot and it doesn't show so many warnings. Why am I getting those warning. Do I need to resolve them for a smooth execution?
c:\spark-1.6.1-bin-hadoop2.6\spark-1.6.1-bin-hadoop2.6>bin\spark-shell
Picked up _JAVA_OPTIONS: -Djava.net.preferIPv4Stack=true
Picked up _JAVA_OPTIONS: -Djava.net.preferIPv4Stack=true
16/03/16 08:12:59 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Welcome to
____ __
/ __/__ ___ _____/ /__
_\ \/ _ \/ _ `/ __/ '_/
/___/ .__/\_,_/_/ /_/\_\ version 1.6.1
/_/
Using Scala version 2.10.5 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_65)
Type in expressions to have them evaluated.
Type :help for more information.
Spark context available as sc.
16/03/16 08:13:09 WARN General: Plugin (Bundle) "org.datanucleus.store.rdbms" is already registered. Ensure you dont have multiple JAR versions of the same plugin in the classpath. The URL "file:/c:/spark-1.6.1-bin-hado
p2.6/spark-1.6.1-bin-hadoop2.6/bin/../lib/datanucleus-rdbms-3.2.9.jar" is already registered, and you are trying to register an identical plugin located at URL "file:/C:/spark-1.6.1-bin-hadoop2.6/spark-1.6.1-bin-hadoop2
6/lib/datanucleus-rdbms-3.2.9.jar."
16/03/16 08:13:09 WARN General: Plugin (Bundle) "org.datanucleus.api.jdo" is already registered. Ensure you dont have multiple JAR versions of the same plugin in the classpath. The URL "file:/C:/spark-1.6.1-bin-hadoop2.
/spark-1.6.1-bin-hadoop2.6/lib/datanucleus-api-jdo-3.2.6.jar" is already registered, and you are trying to register an identical plugin located at URL "file:/c:/spark-1.6.1-bin-hadoop2.6/spark-1.6.1-bin-hadoop2.6/bin/..
lib/datanucleus-api-jdo-3.2.6.jar."
16/03/16 08:13:09 WARN General: Plugin (Bundle) "org.datanucleus" is already registered. Ensure you dont have multiple JAR versions of the same plugin in the classpath. The URL "file:/C:/spark-1.6.1-bin-hadoop2.6/spark-
.6.1-bin-hadoop2.6/lib/datanucleus-core-3.2.10.jar" is already registered, and you are trying to register an identical plugin located at URL "file:/c:/spark-1.6.1-bin-hadoop2.6/spark-1.6.1-bin-hadoop2.6/bin/../lib/datan
cleus-core-3.2.10.jar."
16/03/16 08:13:09 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies)
16/03/16 08:13:09 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies)
16/03/16 08:13:14 WARN ObjectStore: Version information not found in metastore. hive.metastore.schema.verification is not enabled so recording the schema version 1.2.0
16/03/16 08:13:14 WARN ObjectStore: Failed to get database default, returning NoSuchObjectException
16/03/16 08:13:15 WARN : Your hostname, njog-MOBL1 resolves to a loopback/non-reachable address: 192.168.56.1, but we couldn't find any external IP address!
16/03/16 08:13:22 WARN General: Plugin (Bundle) "org.datanucleus.store.rdbms" is already registered. Ensure you dont have multiple JAR versions of the same plugin in the classpath. The URL "file:/c:/spark-1.6.1-bin-hado
p2.6/spark-1.6.1-bin-hadoop2.6/bin/../lib/datanucleus-rdbms-3.2.9.jar" is already registered, and you are trying to register an identical plugin located at URL "file:/C:/spark-1.6.1-bin-hadoop2.6/spark-1.6.1-bin-hadoop2
6/lib/datanucleus-rdbms-3.2.9.jar."
16/03/16 08:13:22 WARN General: Plugin (Bundle) "org.datanucleus.api.jdo" is already registered. Ensure you dont have multiple JAR versions of the same plugin in the classpath. The URL "file:/C:/spark-1.6.1-bin-hadoop2.
/spark-1.6.1-bin-hadoop2.6/lib/datanucleus-api-jdo-3.2.6.jar" is already registered, and you are trying to register an identical plugin located at URL "file:/c:/spark-1.6.1-bin-hadoop2.6/spark-1.6.1-bin-hadoop2.6/bin/..
lib/datanucleus-api-jdo-3.2.6.jar."
16/03/16 08:13:22 WARN General: Plugin (Bundle) "org.datanucleus" is already registered. Ensure you dont have multiple JAR versions of the same plugin in the classpath. The URL "file:/C:/spark-1.6.1-bin-hadoop2.6/spark-
.6.1-bin-hadoop2.6/lib/datanucleus-core-3.2.10.jar" is already registered, and you are trying to register an identical plugin located at URL "file:/c:/spark-1.6.1-bin-hadoop2.6/spark-1.6.1-bin-hadoop2.6/bin/../lib/datan
cleus-core-3.2.10.jar."
16/03/16 08:13:22 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies)
16/03/16 08:13:22 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies)
SQL context available as sqlContext.