fix: handle loading of complex types into CometVector correctly in iceberg_compat scans

common/src/main/java/org/apache/comet/parquet/AbstractColumnReader.java

@@ -23,6 +23,7 @@
 import org.slf4j.LoggerFactory;
 
 import org.apache.parquet.column.ColumnDescriptor;
+import org.apache.parquet.schema.Type;
 import org.apache.spark.sql.types.DataType;
 import org.apache.spark.sql.types.TimestampNTZType$;
 
@@ -36,6 +37,9 @@ public abstract class AbstractColumnReader implements AutoCloseable {
   /** The Spark data type. */
   protected final DataType type;
 
+  /** The Spark data type. */
+  protected final Type fieldType;
+
   /** Parquet column descriptor. */
   protected final ColumnDescriptor descriptor;
 
@@ -61,13 +65,23 @@ public abstract class AbstractColumnReader implements AutoCloseable {
 
   public AbstractColumnReader(
       DataType type,
+      Type fieldType,
       ColumnDescriptor descriptor,
       boolean useDecimal128,
       boolean useLegacyDateTimestamp) {
     this.type = type;
+    this.fieldType = fieldType;
     this.descriptor = descriptor;
     this.useDecimal128 = useDecimal128;
     this.useLegacyDateTimestamp = useLegacyDateTimestamp;
+  }
+
+  public AbstractColumnReader(
+      DataType type,
+      ColumnDescriptor descriptor,
+      boolean useDecimal128,
+      boolean useLegacyDateTimestamp) {
+    this(type, null, descriptor, useDecimal128, useLegacyDateTimestamp);
     TypeUtil.checkParquetType(descriptor, type);
   }
 

common/src/main/java/org/apache/comet/parquet/NativeBatchReader.java

@@ -72,6 +72,7 @@
 import org.apache.comet.shims.ShimBatchReader;
 import org.apache.comet.shims.ShimFileFormat;
 import org.apache.comet.vector.CometVector;
+import org.apache.comet.vector.NativeUtil;
 
 /**
  * A vectorized Parquet reader that reads a Parquet file in a batched fashion.
@@ -94,6 +95,7 @@
 public class NativeBatchReader extends RecordReader<Void, ColumnarBatch> implements Closeable {
   private static final Logger LOG = LoggerFactory.getLogger(NativeBatchReader.class);
   protected static final BufferAllocator ALLOCATOR = new RootAllocator();
+  private NativeUtil nativeUtil = new NativeUtil();
 
   private Configuration conf;
   private int capacity;
@@ -266,7 +268,8 @@ public void init() throws URISyntaxException, IOException {
 
     //// Create Column readers
     List<ColumnDescriptor> columns = requestedSchema.getColumns();
-    int numColumns = columns.size();
+    List<Type> fields = requestedSchema.getFields();
+    int numColumns = fields.size();
     if (partitionSchema != null) numColumns += partitionSchema.size();
     columnReaders = new AbstractColumnReader[numColumns];
 
@@ -454,6 +457,7 @@ public void close() throws IOException {
       importer.close();
       importer = null;
     }
+    nativeUtil.close();
     Native.closeRecordBatchReader(this.handle);
   }
 
@@ -469,19 +473,23 @@ private int loadNextBatch() throws Throwable {
     importer = new CometSchemaImporter(ALLOCATOR);
 
     List<ColumnDescriptor> columns = requestedSchema.getColumns();
-    for (int i = 0; i < columns.size(); i++) {
+    List<Type> fields = requestedSchema.getFields();
+    for (int i = 0; i < fields.size(); i++) {
       // TODO: (ARROW NATIVE) check this. Currently not handling missing columns correctly?
       if (missingColumns[i]) continue;
       if (columnReaders[i] != null) columnReaders[i].close();
       // TODO: (ARROW NATIVE) handle tz, datetime & int96 rebase
       DataType dataType = sparkSchema.fields()[i].dataType();
+      Type field = fields.get(i);
       NativeColumnReader reader =
           new NativeColumnReader(
               this.handle,
               i,
               dataType,
-              columns.get(i),
+              field,
+              null,
               importer,
+              nativeUtil,
               capacity,
               useDecimal128,
               useLegacyDateTimestamp);

common/src/main/java/org/apache/comet/parquet/NativeColumnReader.java

@@ -27,12 +27,8 @@
 import org.apache.arrow.c.CometSchemaImporter;
 import org.apache.arrow.memory.BufferAllocator;
 import org.apache.arrow.memory.RootAllocator;
-import org.apache.arrow.vector.FieldVector;
-import org.apache.arrow.vector.dictionary.Dictionary;
-import org.apache.arrow.vector.types.pojo.DictionaryEncoding;
 import org.apache.parquet.column.ColumnDescriptor;
-import org.apache.parquet.column.page.*;
-import org.apache.parquet.schema.LogicalTypeAnnotation;
+import org.apache.parquet.schema.Type;
 import org.apache.spark.sql.types.DataType;
 
 import org.apache.comet.vector.*;
@@ -65,6 +61,7 @@ public class NativeColumnReader extends AbstractColumnReader {
   boolean hadNull;
 
   private final CometSchemaImporter importer;
+  private final NativeUtil nativeUtil;
 
   private ArrowArray array = null;
   private ArrowSchema schema = null;
@@ -76,14 +73,17 @@ public NativeColumnReader(
       long nativeBatchHandle,
       int columnNum,
       DataType type,
+      Type fieldType,
       ColumnDescriptor descriptor,
       CometSchemaImporter importer,
+      NativeUtil nativeUtil,
       int batchSize,
       boolean useDecimal128,
       boolean useLegacyDateTimestamp) {
-    super(type, descriptor, useDecimal128, useLegacyDateTimestamp);
+    super(type, fieldType, descriptor, useDecimal128, useLegacyDateTimestamp);
     assert batchSize > 0 : "Batch size must be positive, found " + batchSize;
     this.batchSize = batchSize;
+    this.nativeUtil = nativeUtil;
     this.importer = importer;
     this.nativeBatchHandle = nativeBatchHandle;
     this.columnNum = columnNum;
@@ -94,13 +94,13 @@ public NativeColumnReader(
   // Override in order to avoid creation of JVM side column readers
   protected void initNative() {
     LOG.debug(
-        "Native column reader " + String.join(".", this.descriptor.getPath()) + " is initialized");
+        "Native column reader {} is initialized", String.join(".", this.type.catalogString()));
     nativeHandle = 0;
   }
 
   @Override
   public void readBatch(int total) {
-    LOG.debug("Reading column batch of size = " + total);
+    LOG.debug("Reading column batch of size = {}", total);
 
     this.currentNumValues = total;
   }
@@ -131,10 +131,7 @@ public CometDecodedVector loadVector() {
       currentVector.close();
     }
 
-    LogicalTypeAnnotation logicalTypeAnnotation =
-        descriptor.getPrimitiveType().getLogicalTypeAnnotation();
-    boolean isUuid =
-        logicalTypeAnnotation instanceof LogicalTypeAnnotation.UUIDLogicalTypeAnnotation;
+    // TODO: ARROW NATIVE : Handle Uuid?
 
     array = ArrowArray.allocateNew(ALLOCATOR);
     schema = ArrowSchema.allocateNew(ALLOCATOR);
@@ -144,47 +141,19 @@ public CometDecodedVector loadVector() {
 
     Native.currentColumnBatch(nativeBatchHandle, columnNum, arrayAddr, schemaAddr);
 
-    FieldVector vector = importer.importVector(array, schema);
+    ArrowArray[] arrays = {array};
+    ArrowSchema[] schemas = {schema};
 
-    DictionaryEncoding dictionaryEncoding = vector.getField().getDictionary();
-
-    CometPlainVector cometVector = new CometPlainVector(vector, useDecimal128);
+    CometDecodedVector cometVector =
+        (CometDecodedVector)
+            scala.collection.JavaConverters.seqAsJavaList(nativeUtil.importVector(arrays, schemas))
+                .get(0);
 
     // Update whether the current vector contains any null values. This is used in the following
     // batch(s) to determine whether we can skip loading the native vector.
     hadNull = cometVector.hasNull();
 
-    if (dictionaryEncoding == null) {
-      if (dictionary != null) {
-        // This means the column was using dictionary encoding but now has fall-back to plain
-        // encoding, on the native side. Setting 'dictionary' to null here, so we can use it as
-        // a condition to check if we can re-use vector later.
-        dictionary = null;
-      }
-      // Either the column is not dictionary encoded, or it was using dictionary encoding but
-      // a new data page has switched back to use plain encoding. For both cases we should
-      // return plain vector.
-      currentVector = cometVector;
-      return currentVector;
-    }
-
-    // We should already re-initiate `CometDictionary` here because `Data.importVector` API will
-    // release the previous dictionary vector and create a new one.
-    Dictionary arrowDictionary = importer.getProvider().lookup(dictionaryEncoding.getId());
-    CometPlainVector dictionaryVector =
-        new CometPlainVector(arrowDictionary.getVector(), useDecimal128, isUuid);
-    if (dictionary != null) {
-      dictionary.setDictionaryVector(dictionaryVector);
-    } else {
-      dictionary = new CometDictionary(dictionaryVector);
-    }
-
-    currentVector =
-        new CometDictionaryVector(
-            cometVector, dictionary, importer.getProvider(), useDecimal128, false, isUuid);
-
-    currentVector =
-        new CometDictionaryVector(cometVector, dictionary, importer.getProvider(), useDecimal128);
+    currentVector = cometVector;
     return currentVector;
   }
 }

common/src/main/java/org/apache/comet/vector/CometVector.java

@@ -232,7 +232,7 @@ public DictionaryProvider getDictionaryProvider() {
    * @param useDecimal128 Whether to use Decimal128 for decimal column
    * @return `CometVector` implementation
    */
-  protected static CometVector getVector(
+  public static CometVector getVector(
       ValueVector vector, boolean useDecimal128, DictionaryProvider dictionaryProvider) {
     if (vector instanceof StructVector) {
       return new CometStructVector(vector, useDecimal128, dictionaryProvider);