[SPARK-51269][SQL] Simplify AvroCompressionCodec by removing defaultCompressionLevel

### What changes were proposed in this pull request?
This PR proposes to let SQLConf manage the default value for avro compression level.

### Why are the changes needed?
Currently, the default value of `spark.sql.avro.deflate.level` is -1. But it managed with the enum `AvroCompressionCodec`.
The document of the config item `spark.sql.avro.deflate.level` contains the description `The default value is -1 which corresponds to 6 level in the current implementation.` So the users get the knowledge that it has the default value -1.
If some developer use the config item in mistake, there is no guarantee for the default value. And then causes some unpredictable behavior and make users confused.
I think we should keep the default value within `SQLConf` in safety.

Some other config item has the same confusion, `spark.sql.avro.xz.level` and `spark.sql.avro.zstandard.level`.

### Does this PR introduce _any_ user-facing change?
'No'.
New feature.

### How was this patch tested?
GA.

### Was this patch authored or co-authored using generative AI tooling?
'No'.

Closes #50021 from beliefer/SPARK-51269.

Lead-authored-by: beliefer <beliefer@163.com>
Co-authored-by: Kent Yao <yao@apache.org>
Signed-off-by: beliefer <beliefer@163.com>
(cherry picked from commit ef4cd39)
Signed-off-by: beliefer <beliefer@163.com>

Author: beliefer

sql/catalyst/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala

@@ -21,14 +21,14 @@ import java.util.{Locale, Properties, TimeZone}
 import java.util
 import java.util.concurrent.TimeUnit
 import java.util.concurrent.atomic.AtomicReference
-import java.util.zip.Deflater
 
 import scala.collection.immutable
 import scala.jdk.CollectionConverters._
 import scala.util.Try
 import scala.util.control.NonFatal
 import scala.util.matching.Regex
 
+import org.apache.avro.file.CodecFactory
 import org.apache.hadoop.fs.Path
 import org.apache.hadoop.mapreduce.OutputCommitter
 
@@ -4210,8 +4210,8 @@ object SQLConf {
       "The default value is -1 which corresponds to 6 level in the current implementation.")
     .version("2.4.0")
     .intConf
-    .checkValues((1 to 9).toSet + Deflater.DEFAULT_COMPRESSION)
-    .createOptional
+    .checkValues((1 to 9).toSet + CodecFactory.DEFAULT_DEFLATE_LEVEL)
+    .createWithDefault(CodecFactory.DEFAULT_DEFLATE_LEVEL)
 
   val AVRO_XZ_LEVEL = buildConf("spark.sql.avro.xz.level")
     .doc("Compression level for the xz codec used in writing of AVRO files. " +
@@ -4220,14 +4220,13 @@ object SQLConf {
     .version("4.0.0")
     .intConf
     .checkValue(v => v > 0 && v <= 9, "The value must be in the range of from 1 to 9 inclusive.")
-    .createOptional
+    .createWithDefault(CodecFactory.DEFAULT_XZ_LEVEL)
 
   val AVRO_ZSTANDARD_LEVEL = buildConf("spark.sql.avro.zstandard.level")
-    .doc("Compression level for the zstandard codec used in writing of AVRO files. " +
-      "The default value is 3.")
+    .doc("Compression level for the zstandard codec used in writing of AVRO files. ")
     .version("4.0.0")
     .intConf
-    .createOptional
+    .createWithDefault(CodecFactory.DEFAULT_ZSTANDARD_LEVEL)
 
   val AVRO_ZSTANDARD_BUFFER_POOL_ENABLED = buildConf("spark.sql.avro.zstandard.bufferPool.enabled")
     .doc("If true, enable buffer pool of ZSTD JNI library when writing of AVRO files")

sql/core/src/main/java/org/apache/spark/sql/avro/AvroCompressionCodec.java

@@ -22,29 +22,27 @@
 import java.util.Map;
 import java.util.stream.Collectors;
 
-import org.apache.avro.file.*;
+import org.apache.avro.file.DataFileConstants;
 
 /**
  * A mapper class from Spark supported avro compression codecs to avro compression codecs.
  */
 public enum AvroCompressionCodec {
-  UNCOMPRESSED(DataFileConstants.NULL_CODEC, false, -1),
-  DEFLATE(DataFileConstants.DEFLATE_CODEC, true, CodecFactory.DEFAULT_DEFLATE_LEVEL),
-  SNAPPY(DataFileConstants.SNAPPY_CODEC, false, -1),
-  BZIP2(DataFileConstants.BZIP2_CODEC, false, -1),
-  XZ(DataFileConstants.XZ_CODEC, true, CodecFactory.DEFAULT_XZ_LEVEL),
-  ZSTANDARD(DataFileConstants.ZSTANDARD_CODEC, true, CodecFactory.DEFAULT_ZSTANDARD_LEVEL);
+  UNCOMPRESSED(DataFileConstants.NULL_CODEC, false),
+  DEFLATE(DataFileConstants.DEFLATE_CODEC, true),
+  SNAPPY(DataFileConstants.SNAPPY_CODEC, false),
+  BZIP2(DataFileConstants.BZIP2_CODEC, false),
+  XZ(DataFileConstants.XZ_CODEC, true),
+  ZSTANDARD(DataFileConstants.ZSTANDARD_CODEC, true);
 
   private final String codecName;
   private final boolean supportCompressionLevel;
-  private final int defaultCompressionLevel;
 
   AvroCompressionCodec(
       String codecName,
-      boolean supportCompressionLevel, int defaultCompressionLevel) {
+      boolean supportCompressionLevel) {
     this.codecName = codecName;
     this.supportCompressionLevel = supportCompressionLevel;
-    this.defaultCompressionLevel = defaultCompressionLevel;
   }
 
   public String getCodecName() {
@@ -55,10 +53,6 @@ public boolean getSupportCompressionLevel() {
     return this.supportCompressionLevel;
   }
 
-  public int getDefaultCompressionLevel() {
-    return this.defaultCompressionLevel;
-  }
-
   private static final Map<String, String> codecNameMap =
     Arrays.stream(AvroCompressionCodec.values()).collect(
       Collectors.toMap(codec -> codec.name(), codec -> codec.name().toLowerCase(Locale.ROOT)));

sql/core/src/main/scala/org/apache/spark/sql/avro/AvroUtils.scala

@@ -121,18 +121,20 @@ private[sql] object AvroUtils extends Logging {
             jobConf.setBoolean("mapreduce.output.fileoutputformat.compress", true)
             jobConf.set(AvroJob.CONF_OUTPUT_CODEC, compressed.getCodecName)
             if (compressed.getSupportCompressionLevel) {
-              val level = sqlConf.getConfString(s"spark.sql.avro.$codecName.level",
-                compressed.getDefaultCompressionLevel.toString)
-              logInfo(log"Compressing Avro output using the ${MDC(CODEC_NAME, codecName)} codec " +
-                log"at level ${MDC(CODEC_LEVEL, level)}")
-              val s = if (compressed == ZSTANDARD) {
-                val bufferPoolEnabled = sqlConf.getConf(SQLConf.AVRO_ZSTANDARD_BUFFER_POOL_ENABLED)
-                jobConf.setBoolean(AvroOutputFormat.ZSTD_BUFFERPOOL_KEY, bufferPoolEnabled)
-                "zstd"
-              } else {
-                codecName
+              val levelAndCodecName = compressed match {
+                case DEFLATE => Some(sqlConf.getConf(SQLConf.AVRO_DEFLATE_LEVEL), codecName)
+                case XZ => Some(sqlConf.getConf(SQLConf.AVRO_XZ_LEVEL), codecName)
+                case ZSTANDARD =>
+                  jobConf.setBoolean(AvroOutputFormat.ZSTD_BUFFERPOOL_KEY,
+                    sqlConf.getConf(SQLConf.AVRO_ZSTANDARD_BUFFER_POOL_ENABLED))
+                  Some(sqlConf.getConf(SQLConf.AVRO_ZSTANDARD_LEVEL), "zstd")
+                case _ => None
+              }
+              levelAndCodecName.foreach { case (level, mapredCodecName) =>
+                logInfo(log"Compressing Avro output using the ${MDC(CODEC_NAME, codecName)} " +
+                  log"codec at level ${MDC(CODEC_LEVEL, level)}")
+                jobConf.setInt(s"avro.mapred.$mapredCodecName.level", level.toInt)
               }
-              jobConf.setInt(s"avro.mapred.$s.level", level.toInt)
             } else {
               logInfo(log"Compressing Avro output using the ${MDC(CODEC_NAME, codecName)} codec")
             }