what does maven dependency in spark show me the missing artifact errors?

Question

I would like to install Spark from the Maven Central, and I included the following dependency:

<dependency>
  <groupId>org.apache.spark</groupId>
  <artifactId>spark-core_2.10</artifactId>
  <version>1.0.2</version>
</dependency>

But I got this following 22 errors. Summarizing, it says I am missing the artifacts com.clearspring.analytics.stream:jar.2.5.1 and org.scala-lang:scala-compiler:jar2.10.0. I included each of the jar files by including them in my project (external jar files), but it didn't work at all. And I know that I have Scala 2.11 installed, so having the higher version is no big issue.

Can anybody tell me what is going on?

This is the following errors:

Description Resource    Path    Location    Type

ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from http://repo.maven.apache.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of central has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to central (http://repo.maven.apache.org/maven2): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from http://repo.maven.apache.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of maven-repo has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to central (http://repo.maven.apache.org/maven2): The operation was cancelled. pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from http://repo.spring.io/libs-release was cached in the local repository, resolution will not be reattempted until the update interval of spring-releases has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to spring-releases (http://repo.spring.io/libs-release): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from http://repository.mapr.com/maven was cached in the local repository, resolution will not be reattempted until the update interval of mapr-repo has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to mapr-repo (http://repository.mapr.com/maven): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from https://repo.eclipse.org/content/repositories/paho-releases was cached in the local repository, resolution will not be reattempted until the update interval of mqtt-repo has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to mqtt-repo (https://repo.eclipse.org/content/repositories/paho-releases): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from https://repository.apache.org/content/repositories/releases was cached in the local repository, resolution will not be reattempted until the update interval of apache-repo has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to apache-repo (https://repository.apache.org/content/repositories/releases): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from https://repository.cloudera.com/artifactory/cloudera-repos was cached in the local repository, resolution will not be reattempted until the update interval of cloudera-repo has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to cloudera-repo (https://repository.cloudera.com/artifactory/cloudera-repos): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer com.clearspring.analytics:stream:jar:2.5.1 from https://repository.jboss.org/nexus/content/repositories/releases was cached in the local repository, resolution will not be reattempted until the update interval of jboss-repo has elapsed or updates are forced. Original error: Could not transfer artifact com.clearspring.analytics:stream:jar:2.5.1 from/to jboss-repo (https://repository.jboss.org/nexus/content/repositories/releases): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from http://repo.maven.apache.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of central has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to central (http://repo.maven.apache.org/maven2): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from http://repo.maven.apache.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of maven-repo has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to central (http://repo.maven.apache.org/maven2): The operation was cancelled. pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from http://repo.spring.io/libs-release was cached in the local repository, resolution will not be reattempted until the update interval of spring-releases has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to spring-releases (http://repo.spring.io/libs-release): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from http://repository.mapr.com/maven was cached in the local repository, resolution will not be reattempted until the update interval of mapr-repo has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to mapr-repo (http://repository.mapr.com/maven): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from https://oss.sonatype.org/content/repositories/releases/ was cached in the local repository, resolution will not be reattempted until the update interval of sonatypereleases has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to sonatypereleases (https://oss.sonatype.org/content/repositories/releases/): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from https://oss.sonatype.org/content/repositories/snapshots/ was cached in the local repository, resolution will not be reattempted until the update interval of sonatypesnapshots has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to sonatypesnapshots (https://oss.sonatype.org/content/repositories/snapshots/): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from https://repo.eclipse.org/content/repositories/paho-releases was cached in the local repository, resolution will not be reattempted until the update interval of mqtt-repo has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to mqtt-repo (https://repo.eclipse.org/content/repositories/paho-releases): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from https://repository.apache.org/content/repositories/releases was cached in the local repository, resolution will not be reattempted until the update interval of apache-repo has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to apache-repo (https://repository.apache.org/content/repositories/releases): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from https://repository.cloudera.com/artifactory/cloudera-repos was cached in the local repository, resolution will not be reattempted until the update interval of cloudera-repo has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to cloudera-repo (https://repository.cloudera.com/artifactory/cloudera-repos): The operation was cancelled.  pom.xml /recommendation_engine  line 2  Maven Dependency Problem
ArtifactTransferException: Failure to transfer org.scala-lang:scala-compiler:jar:2.10.0 from https://repository.jboss.org/nexus/content/repositories/releases was cached in the local repository, resolution will not be reattempted until the update interval of jboss-repo has elapsed or updates are forced. Original error: Could not transfer artifact org.scala-lang:scala-compiler:jar:2.10.0 from/to jboss-repo (https://repository.jboss.org/nexus/content/repositories/releases): The operation was cancelled.    pom.xml /recommendation_engine  line 2  Maven Dependency Problem
Missing artifact com.clearspring.analytics:stream:jar:2.5.1 pom.xml /recommendation_engine  line 1  Maven Dependency Problem
Missing artifact org.scala-lang:scala-compiler:jar:2.10.0   pom.xml /recommendation_engine  line 1  Maven Dependency Problem
The container 'Maven Dependencies' references non existing library '/Users/chlee021690/.m2/repository/org/scala-lang/scala-compiler/2.10.0/scala-compiler-2.10.0.jar'   recommendation_engine       Build path  Build Path Problem
The project cannot be built until build path errors are resolved    recommendation_engine       Unknown Java Problem

Answer 1

If you are behind a proxy you might have to specify the proxy in the settings.xml. From the error messages it seems your maven instance is not able to connect to maven central. See this for setting up a proxy: http://maven.apache.org/guides/mini/guide-proxies.html