[SPARK-9368][SQL] Support get(ordinal, dataType) generic getter in UnsafeRow.

Author: rxin

sql/catalyst/src/main/java/org/apache/spark/sql/catalyst/expressions/UnsafeRow.java

@@ -24,7 +24,7 @@
 import java.util.HashSet;
 import java.util.Set;
 
-import org.apache.spark.sql.types.DataType;
+import org.apache.spark.sql.types.*;
 import org.apache.spark.unsafe.PlatformDependent;
 import org.apache.spark.unsafe.array.ByteArrayMethods;
 import org.apache.spark.unsafe.bitset.BitSetMethods;
@@ -235,6 +235,35 @@ public Object get(int ordinal) {
     throw new UnsupportedOperationException();
   }
 
+  @Override
+  public Object get(int ordinal, DataType dataType) {
+    if (dataType instanceof NullType) {
+      return null;
+    } else if (dataType instanceof BooleanType) {
+      return getBoolean(ordinal);
+    } else if (dataType instanceof ByteType) {
+      return getByte(ordinal);
+    } else if (dataType instanceof ShortType) {
+      return getShort(ordinal);
+    } else if (dataType instanceof IntegerType) {
+      return getInt(ordinal);
+    } else if (dataType instanceof LongType) {
+      return getLong(ordinal);
+    } else if (dataType instanceof FloatType) {
+      return getFloat(ordinal);
+    } else if (dataType instanceof DoubleType) {
+      return getDouble(ordinal);
+    } else if (dataType instanceof DecimalType) {
+      return getDecimal(ordinal);
+    } else if (dataType instanceof StringType) {
+      return getUTF8String(ordinal);
+    } else if (dataType instanceof StructType) {
+      return getStruct(ordinal, ((StructType) dataType).size());
+    } else {
+      throw new UnsupportedOperationException("Unsupported data type " + dataType.simpleString());
+    }
+  }
+
   @Override
   public boolean isNullAt(int ordinal) {
     assertIndexIsValid(ordinal);
@@ -436,4 +465,19 @@ public String toString() {
   public boolean anyNull() {
     return BitSetMethods.anySet(baseObject, baseOffset, bitSetWidthInBytes / 8);
   }
+
+  /**
+   * Writes the content of this row into a memory address, identified by an object and an offset.
+   * The target memory address must already been allocated, and have enough space to hold all the
+   * bytes in this string.
+   */
+  public void writeToMemory(Object target, long targetOffset) {
+    PlatformDependent.copyMemory(
+      baseObject,
+      baseOffset,
+      target,
+      targetOffset,
+      sizeInBytes
+    );
+  }
 }

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/InternalRow.scala

@@ -30,11 +30,11 @@ abstract class InternalRow extends Serializable {
 
   def numFields: Int
 
-  def get(ordinal: Int): Any
+  def get(ordinal: Int): Any = get(ordinal, null)
 
   def genericGet(ordinal: Int): Any = get(ordinal, null)
 
-  def get(ordinal: Int, dataType: DataType): Any = get(ordinal)
+  def get(ordinal: Int, dataType: DataType): Any
 
   def getAs[T](ordinal: Int, dataType: DataType): T = get(ordinal, dataType).asInstanceOf[T]
 

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SpecificMutableRow.scala

@@ -219,7 +219,7 @@ final class SpecificMutableRow(val values: Array[MutableValue]) extends MutableR
     values(i).isNull = true
   }
 
-  override def get(i: Int): Any = values(i).boxed
+  override def get(i: Int, dataType: DataType): Any = values(i).boxed
 
   override def getStruct(ordinal: Int, numFields: Int): InternalRow = {
     values(ordinal).boxed.asInstanceOf[InternalRow]

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

@@ -183,7 +183,7 @@ object GenerateProjection extends CodeGenerator[Seq[Expression], Projection] {
         public void setNullAt(int i) { nullBits[i] = true; }
         public boolean isNullAt(int i) { return nullBits[i]; }
 
-        public Object get(int i) {
+        public Object get(int i, ${classOf[DataType].getName} dataType) {
           if (isNullAt(i)) return null;
           switch (i) {
           $getCases

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/rows.scala

@@ -99,7 +99,7 @@ class GenericInternalRow(protected[sql] val values: Array[Any]) extends Internal
 
   override def numFields: Int = values.length
 
-  override def get(i: Int): Any = values(i)
+  override def get(i: Int, dataType: DataType): Any = values(i)
 
   override def getStruct(ordinal: Int, numFields: Int): InternalRow = {
     values(ordinal).asInstanceOf[InternalRow]
@@ -130,7 +130,7 @@ class GenericMutableRow(val values: Array[Any]) extends MutableRow {
 
   override def numFields: Int = values.length
 
-  override def get(i: Int): Any = values(i)
+  override def get(i: Int, dataType: DataType): Any = values(i)
 
   override def getStruct(ordinal: Int, numFields: Int): InternalRow = {
     values(ordinal).asInstanceOf[InternalRow]