MapR [SPARK-170] StackOverflowException in equals method in DBMapValue (apache#233)

Author: ekrivokonmapr

external/maprdb/pom.xml

@@ -26,6 +26,13 @@
       <version>${project.version}</version>
       <scope>provided</scope>
     </dependency>
+    <dependency>
+        <groupId>org.apache.spark</groupId>
+        <artifactId>spark-core_${scala.binary.version}</artifactId>
+        <version>${project.version}</version>
+        <type>test-jar</type>
+        <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>org.apache.spark</groupId>
       <artifactId>spark-streaming_${scala.binary.version}</artifactId>

external/maprdb/src/main/scala/com/mapr/db/spark/types/DBMapValue.scala

@@ -67,14 +67,12 @@ private[spark] final class DBMapValue(
   override def hashCode(): Int = this.keySet.size
 
   override def equals(other: Any): Boolean = {
-    if (other.isInstanceOf[DBMapValue]) {
-      val that: DBMapValue = other.asInstanceOf[DBMapValue]
-      this == that
-    } else if (other.isInstanceOf[Map[_, _]]) {
-      val that: DBMapValue = new DBMapValue(
-        other.asInstanceOf[Map[String, AnyRef]])
-      this.getMap == that
-    } else false
-
+    other match {
+      case _: Map[_, _] =>
+        val that: DBMapValue = new DBMapValue(
+          other.asInstanceOf[Map[String, AnyRef]])
+        this.getMap == that
+      case _ => false
+    }
   }
 }

external/maprdb/src/test/scala/com/mapr/db/spark/types/DBMapValueTest.scala

@@ -0,0 +1,16 @@
+/* Copyright (c) 2015 & onwards. MapR Tech, Inc., All rights reserved */
+package com.mapr.db.spark.types
+
+import org.apache.spark.SparkFunSuite
+
+class DBMapValueTest extends SparkFunSuite {
+  test("Check DBMapValue equals method") {
+    val map = Map("1" -> "2", "a" -> "b")
+    val dbMapValue = new DBMapValue(map)
+    val dbMapValueOther = new DBMapValue(map)
+
+    assert(!dbMapValue.equals("StringType"))
+    assert(dbMapValue.equals(map))
+    assert(dbMapValue.equals(dbMapValueOther))
+  }
+}