[CARBONDATA-3119] Fixing the getOrCreateCarbonSession method paramete…

…r to an empty string

Fixing the getOrCreateCarbonSession method parameter to an empty string causes the select table data to be empty

problem: When create carbonSession in this way: [val carbon = SparkSession.builder().config(sc.getConf).getOrCreateCarbonSession("")],The prompt can be created successfully, with no exceptions thrown during the process, but ultimately [carbon.sql("SELECT * FROM TABLE").show()] is empty.

cause: [carbon.sql("SELECT * FROM TABLE").show()] is empty.

solution: Increases the null or empty judgment of getOrCreateCarbonSession method  parameters[storePath,metaStorePath]

This closes #2961

integration/spark2/src/main/scala/org/apache/spark/sql/CarbonSession.scala

@@ -21,6 +21,7 @@ import java.util.concurrent.atomic.AtomicLong
 
 import scala.collection.JavaConverters._
 
+import org.apache.commons.lang.StringUtils
 import org.apache.hadoop.conf.Configuration
 import org.apache.spark.{SparkConf, SparkContext}
 import org.apache.spark.sql.SparkSession.Builder
@@ -180,7 +181,7 @@ object CarbonSession {
       val userSuppliedContext: Option[SparkContext] =
         getValue("userSuppliedContext", builder).asInstanceOf[Option[SparkContext]]
 
-      if (metaStorePath != null) {
+      if (StringUtils.isNotBlank(metaStorePath)) {
         val hadoopConf = new Configuration()
         val configFile = Utils.getContextOrSparkClassLoader.getResource("hive-site.xml")
         if (configFile != null) {
@@ -248,7 +249,7 @@ object CarbonSession {
 
         session = new CarbonSession(sparkContext, None, !enableInMemCatlog)
         val carbonProperties = CarbonProperties.getInstance()
-        if (storePath != null) {
+        if (StringUtils.isNotBlank(storePath)) {
           carbonProperties.addProperty(CarbonCommonConstants.STORE_LOCATION, storePath)
           // In case if it is in carbon.properties for backward compatible
         } else if (carbonProperties.getProperty(CarbonCommonConstants.STORE_LOCATION) == null) {