[SPARK-51874][SQL][FOLLOW-UP] Revert ParquetOptions rebase methods to return string type

### What changes were proposed in this pull request?

This is a followup of #50674 . In that PR, we made it easier to define sql configs with enum values, and we also refactored some code to make things simpler.

This PR reverts the API changes of `ParquetOptions`. Ideally we can change private APIs, but Parquet is a very popular format and there are third-party spark plugins that use Parquet related private APIs in Spark. We can of course ask these Spark plugins to update their code or add shim layers, but it's more friendly to avoid breaking certain private APIs if easy.

### Why are the changes needed?

avoid breaking private APIs that used by Spark plugins, such as https://github.com/apache/hudi/blob/master/hudi-spark-datasource/hudi-spark3.5.x/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/Spark35LegacyHoodieParquetFileFormat.scala#L150

### Does this PR introduce _any_ user-facing change?

no

### How was this patch tested?

N/A

### Was this patch authored or co-authored using generative AI tooling?

no

Closes #52065 from cloud-fan/follow.

Authored-by: Wenchen Fan <[email protected]>
Signed-off-by: Wenchen Fan <[email protected]>

Author: cloud-fan

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetFileFormat.scala

@@ -44,7 +44,7 @@ import org.apache.spark.sql.catalyst.util.DateTimeUtils
 import org.apache.spark.sql.errors.QueryExecutionErrors
 import org.apache.spark.sql.execution.datasources._
 import org.apache.spark.sql.execution.vectorized.{ConstantColumnVector, OffHeapColumnVector, OnHeapColumnVector}
-import org.apache.spark.sql.internal.SQLConf
+import org.apache.spark.sql.internal.{LegacyBehaviorPolicy, SQLConf}
 import org.apache.spark.sql.sources._
 import org.apache.spark.sql.types._
 import org.apache.spark.util.{SerializableConfiguration, ThreadUtils}
@@ -182,8 +182,10 @@ class ParquetFileFormat
     val pushDownInFilterThreshold = sqlConf.parquetFilterPushDownInFilterThreshold
     val isCaseSensitive = sqlConf.caseSensitiveAnalysis
     val parquetOptions = new ParquetOptions(options, sparkSession.sessionState.conf)
-    val datetimeRebaseModeInRead = parquetOptions.datetimeRebaseModeInRead
-    val int96RebaseModeInRead = parquetOptions.int96RebaseModeInRead
+    val datetimeRebaseModeInRead = LegacyBehaviorPolicy.withName(
+      parquetOptions.datetimeRebaseModeInRead)
+    val int96RebaseModeInRead = LegacyBehaviorPolicy.withName(
+      parquetOptions.int96RebaseModeInRead)
 
     // Should always be set by FileSourceScanExec creating this.
     // Check conf before checking option, to allow working around an issue by changing conf.

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetOptions.scala

@@ -24,7 +24,7 @@ import org.apache.parquet.hadoop.ParquetOutputFormat
 import org.apache.spark.sql.catalyst.{DataSourceOptions, FileSourceOptions}
 import org.apache.spark.sql.catalyst.util.CaseInsensitiveMap
 import org.apache.spark.sql.errors.QueryExecutionErrors
-import org.apache.spark.sql.internal.{LegacyBehaviorPolicy, SQLConf}
+import org.apache.spark.sql.internal.SQLConf
 
 /**
  * Options for the Parquet data source.
@@ -74,16 +74,15 @@ class ParquetOptions(
   /**
    * The rebasing mode for the DATE and TIMESTAMP_MICROS, TIMESTAMP_MILLIS values in reads.
    */
-  def datetimeRebaseModeInRead: LegacyBehaviorPolicy.Value = parameters
+  def datetimeRebaseModeInRead: String = parameters
     .get(DATETIME_REBASE_MODE)
-    .map(LegacyBehaviorPolicy.withName)
-    .getOrElse(sqlConf.getConf(SQLConf.PARQUET_REBASE_MODE_IN_READ))
+    .getOrElse(sqlConf.getConf(SQLConf.PARQUET_REBASE_MODE_IN_READ).toString)
   /**
    * The rebasing mode for INT96 timestamp values in reads.
    */
-  def int96RebaseModeInRead: LegacyBehaviorPolicy.Value = parameters
-    .get(INT96_REBASE_MODE).map(LegacyBehaviorPolicy.withName)
-    .getOrElse(sqlConf.getConf(SQLConf.PARQUET_INT96_REBASE_MODE_IN_READ))
+  def int96RebaseModeInRead: String = parameters
+    .get(INT96_REBASE_MODE)
+    .getOrElse(sqlConf.getConf(SQLConf.PARQUET_INT96_REBASE_MODE_IN_READ).toString)
 }
 
 

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/parquet/ParquetPartitionReaderFactory.scala

@@ -38,7 +38,7 @@ import org.apache.spark.sql.execution.WholeStageCodegenExec
 import org.apache.spark.sql.execution.datasources.{AggregatePushDownUtils, DataSourceUtils, PartitionedFile, RecordReaderIterator}
 import org.apache.spark.sql.execution.datasources.parquet._
 import org.apache.spark.sql.execution.datasources.v2._
-import org.apache.spark.sql.internal.SQLConf
+import org.apache.spark.sql.internal.{LegacyBehaviorPolicy, SQLConf}
 import org.apache.spark.sql.sources.Filter
 import org.apache.spark.sql.types.StructType
 import org.apache.spark.sql.vectorized.ColumnarBatch
@@ -81,8 +81,10 @@ case class ParquetPartitionReaderFactory(
   private val pushDownDecimal = sqlConf.parquetFilterPushDownDecimal
   private val pushDownStringPredicate = sqlConf.parquetFilterPushDownStringPredicate
   private val pushDownInFilterThreshold = sqlConf.parquetFilterPushDownInFilterThreshold
-  private val datetimeRebaseModeInRead = options.datetimeRebaseModeInRead
-  private val int96RebaseModeInRead = options.int96RebaseModeInRead
+  private val datetimeRebaseModeInRead = LegacyBehaviorPolicy.withName(
+    options.datetimeRebaseModeInRead)
+  private val int96RebaseModeInRead = LegacyBehaviorPolicy.withName(
+    options.int96RebaseModeInRead)
 
   private val parquetReaderCallback = new ParquetReaderCallback()