title: Error while using SparkSession or sqlcontext
body: <p>I am new to spark. I am just trying to parse a json file using sparksession or sqlcontext. 
  But whenever I run them, I am getting the following error. </p>
  
  <pre><code>Exception in thread "main" java.lang.NoSuchMethodError:
  org.apache.spark.internal.config.package$.CATALOG_IMPLEMENTATION()Lorg/apache/spark/internal/config/ConfigEntry; at
  org.apache.spark.sql.SparkSession$.org$apache$spark$sql$SparkSession$$sessionStateClassName(SparkSession.scala:930) at
  org.apache.spark.sql.SparkSession.sessionState$lzycompute(SparkSession.scala:112) at
  org.apache.spark.sql.SparkSession.sessionState(SparkSession.scala:110)  at 
  org.apache.spark.sql.DataFrameReader.&lt;init&gt;(DataFrameReader.scala:535)  at 
  org.apache.spark.sql.SparkSession.read(SparkSession.scala:595) at
  org.apache.spark.sql.SQLContext.read(SQLContext.scala:504) at
  joinAssetsAndAd$.main(joinAssetsAndAd.scala:21) at
  joinAssetsAndAd.main(joinAssetsAndAd.scala)
  </code></pre>
  
  <p>As of now I created a scala project in eclipse IDE and configured it as Maven project and added the spark and sql dependencies.</p>
  
  <p>My dependencies :</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;dependencies&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.apache.spark&lt;/groupId&gt;
          &lt;artifactId&gt;spark-core_2.11&lt;/artifactId&gt;
          &lt;version&gt;2.1.0&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.apache.spark&lt;/groupId&gt;
          &lt;artifactId&gt;spark-sql_2.11&lt;/artifactId&gt;
          &lt;version&gt;2.0.0&lt;/version&gt;
      &lt;/dependency&gt;
  &lt;/dependencies&gt;
  </code></pre>
  
  <p>Could you please explain why I am getting this error and how to correct them?</p>