Create setValue to update a variable for a given DataType

Author: Yucai Yu

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/codegen/CodeGenerator.scala

@@ -318,6 +318,20 @@ class CodegenContext {
     }
   }
 
+  /**
+   * Returns the code to update a variable for a given DataType.
+   */
+  def setValue(target: String, dataType: DataType, value: String): String = {
+    val jt = javaType(dataType)
+    val codes = dataType match {
+      case _ if isPrimitiveType(jt) => value
+      case StringType => s"$value.clone()"
+      case _: StructType | _: ArrayType | _: MapType => s"$value.copy()"
+      case _ => value
+    }
+    s"$target = $codes"
+  }
+
   /**
    * Returns the specialized code to set a given value in a column vector for a given `DataType`.
    */
@@ -375,16 +389,6 @@ class CodegenContext {
     }
   }
 
-  def copyValue(value: String, dataType: DataType): String = {
-    val jt = javaType(dataType)
-    val safeCopy = s"$value == null ? null :"
-    dataType match {
-      case _ if isPrimitiveType(jt) => value
-      case _: StructType => s"$safeCopy $value.copy()"
-      case _ => s"$safeCopy $value.clone()"
-    }
-  }
-
   /**
    * Returns the name used in accessor and setter for a Java primitive type.
    */

sql/core/src/main/scala/org/apache/spark/sql/execution/aggregate/SortAggregateExec.scala

@@ -186,7 +186,7 @@ case class SortAggregateExec(
       s"""
          | ${bufVars(i).isNull} = ${ev.isNull};
          | if (${bufVars(i).value} != ${ev.value})
-         |     ${bufVars(i).value} = ${ctx.copyValue(ev.value, bufVarsType(i))};
+         |     ${ctx.setValue(bufVars(i).value, bufVarsType(i), ev.value)};
        """.stripMargin
     }
     s"""