Backport to branch(3) : Refactor KeyBytesEncoder to use ColumnVisitor

core/src/main/java/com/scalar/db/storage/dynamo/bytes/BigIntBytesEncoder.java

@@ -3,23 +3,25 @@
 import static com.scalar.db.storage.dynamo.bytes.BytesUtils.mask;
 
 import com.scalar.db.api.Scan.Ordering.Order;
-import com.scalar.db.io.BigIntValue;
+import com.scalar.db.io.BigIntColumn;
 import java.nio.ByteBuffer;
 import javax.annotation.concurrent.ThreadSafe;
 
 @ThreadSafe
-public class BigIntBytesEncoder implements BytesEncoder<BigIntValue> {
+public class BigIntBytesEncoder implements BytesEncoder<BigIntColumn> {
 
   BigIntBytesEncoder() {}
 
   @Override
-  public int encodedLength(BigIntValue value, Order order) {
+  public int encodedLength(BigIntColumn column, Order order) {
     return 8;
   }
 
   @Override
-  public void encode(BigIntValue value, Order order, ByteBuffer dst) {
-    long v = value.getAsLong();
+  public void encode(BigIntColumn column, Order order, ByteBuffer dst) {
+    assert !column.hasNullValue();
+
+    long v = column.getBigIntValue();
     dst.put(mask((byte) ((v >> 56) ^ 0x80), order)); // Flip a sign bit to make it binary comparable
     dst.put(mask((byte) (v >> 48), order));
     dst.put(mask((byte) (v >> 40), order));

core/src/main/java/com/scalar/db/storage/dynamo/bytes/BlobBytesEncoder.java

@@ -4,30 +4,33 @@
 
 import com.scalar.db.api.Scan.Ordering.Order;
 import com.scalar.db.common.error.CoreError;
-import com.scalar.db.io.BlobValue;
+import com.scalar.db.io.BlobColumn;
 import java.nio.ByteBuffer;
 import javax.annotation.concurrent.ThreadSafe;
 
 @ThreadSafe
-public class BlobBytesEncoder implements BytesEncoder<BlobValue> {
+public class BlobBytesEncoder implements BytesEncoder<BlobColumn> {
 
   private static final byte TERM = (byte) 0x00;
   private static final byte MASKED_TERM = (byte) 0xff;
 
   BlobBytesEncoder() {}
 
   @Override
-  public int encodedLength(BlobValue value, Order order) {
-    assert value.getAsBytes().isPresent();
-    return value.getAsBytes().get().length + (order == Order.ASC ? 0 : 1);
+  public int encodedLength(BlobColumn column, Order order) {
+    assert column.getBlobValueAsBytes() != null;
+
+    return column.getBlobValueAsBytes().length + (order == Order.ASC ? 0 : 1);
   }
 
   @Override
-  public void encode(BlobValue value, Order order, ByteBuffer dst) {
-    assert value.getAsBytes().isPresent();
+  public void encode(BlobColumn column, Order order, ByteBuffer dst) {
+    assert column.getBlobValueAsBytes() != null;
+
+    byte[] value = column.getBlobValueAsBytes();
 
     if (order == Order.DESC) {
-      for (byte b : value.getAsBytes().get()) {
+      for (byte b : value) {
         if (b == TERM) {
           throw new IllegalArgumentException(
               CoreError.DYNAMO_ENCODER_0X00_BYTES_NOT_ACCEPTED_IN_BLOB_VALUES_IN_DESC_ORDER
@@ -36,7 +39,7 @@ public void encode(BlobValue value, Order order, ByteBuffer dst) {
       }
     }
 
-    for (byte b : value.getAsBytes().get()) {
+    for (byte b : value) {
       dst.put(mask(b, order));
     }
     if (order == Order.DESC) {

core/src/main/java/com/scalar/db/storage/dynamo/bytes/BooleanBytesEncoder.java

@@ -3,25 +3,27 @@
 import static com.scalar.db.storage.dynamo.bytes.BytesUtils.mask;
 
 import com.scalar.db.api.Scan.Ordering.Order;
-import com.scalar.db.io.BooleanValue;
+import com.scalar.db.io.BooleanColumn;
 import java.nio.ByteBuffer;
 import javax.annotation.concurrent.ThreadSafe;
 
 @ThreadSafe
-public class BooleanBytesEncoder implements BytesEncoder<BooleanValue> {
+public class BooleanBytesEncoder implements BytesEncoder<BooleanColumn> {
   private static final byte FALSE = 0x00;
   private static final byte TRUE = 0x01;
 
   BooleanBytesEncoder() {}
 
   @Override
-  public int encodedLength(BooleanValue value, Order order) {
+  public int encodedLength(BooleanColumn column, Order order) {
     return 1;
   }
 
   @Override
-  public void encode(BooleanValue value, Order order, ByteBuffer dst) {
-    boolean b = value.getAsBoolean();
+  public void encode(BooleanColumn column, Order order, ByteBuffer dst) {
+    assert !column.hasNullValue();
+
+    boolean b = column.getBooleanValue();
     dst.put(mask(b ? TRUE : FALSE, order));
   }
 }

core/src/main/java/com/scalar/db/storage/dynamo/bytes/BytesEncoder.java

@@ -1,31 +1,31 @@
 package com.scalar.db.storage.dynamo.bytes;
 
 import com.scalar.db.api.Scan.Ordering.Order;
-import com.scalar.db.io.Value;
+import com.scalar.db.io.Column;
 import java.nio.ByteBuffer;
 
 /**
- * A bytes-encoder that encodes a value to bytes while preserving the sort order.
+ * A bytes-encoder that encodes a column to bytes while preserving the sort order.
  *
  * @param <T> the value type
  */
-public interface BytesEncoder<T extends Value<?>> {
+public interface BytesEncoder<T extends Column<?>> {
 
   /**
    * Calculates the encoded bytes length.
    *
-   * @param value a value
+   * @param column a column
    * @param order an order
    * @return the encoded bytes length
    */
-  int encodedLength(T value, Order order);
+  int encodedLength(T column, Order order);
 
   /**
-   * Encodes the value to bytes
+   * Encodes the column to bytes
    *
-   * @param value a value
+   * @param column a column
    * @param order an order
    * @param dst a ByteBuffer to write the encoded bytes
    */
-  void encode(T value, Order order, ByteBuffer dst);
+  void encode(T column, Order order, ByteBuffer dst);
 }

core/src/main/java/com/scalar/db/storage/dynamo/bytes/DoubleBytesEncoder.java

@@ -3,22 +3,23 @@
 import static com.scalar.db.storage.dynamo.bytes.BytesUtils.mask;
 
 import com.scalar.db.api.Scan.Ordering.Order;
-import com.scalar.db.io.DoubleValue;
+import com.scalar.db.io.DoubleColumn;
 import java.nio.ByteBuffer;
 import javax.annotation.concurrent.ThreadSafe;
 
 @ThreadSafe
-public class DoubleBytesEncoder implements BytesEncoder<DoubleValue> {
+public class DoubleBytesEncoder implements BytesEncoder<DoubleColumn> {
 
   DoubleBytesEncoder() {}
 
   @Override
-  public int encodedLength(DoubleValue value, Order order) {
+  public int encodedLength(DoubleColumn column, Order order) {
     return 8;
   }
 
   @Override
-  public void encode(DoubleValue value, Order order, ByteBuffer dst) {
+  public void encode(DoubleColumn column, Order order, ByteBuffer dst) {
+    assert !column.hasNullValue();
     /*
      * The IEE754 floating point format already preserves sort ordering for positive floating point
      * numbers when the raw bytes are compared in most significant byte order.
@@ -30,7 +31,7 @@ public void encode(DoubleValue value, Order order, ByteBuffer dst) {
      */
 
     // store the floating point bits into a 64-bit long
-    long l = Double.doubleToLongBits(value.getAsDouble());
+    long l = Double.doubleToLongBits(column.getDoubleValue());
 
     // invert the sign bit and XOR's all other bits with the sign bit itself
     l ^= ((l >> (Long.SIZE - 1)) | Long.MIN_VALUE);

core/src/main/java/com/scalar/db/storage/dynamo/bytes/FloatBytesEncoder.java

@@ -3,22 +3,23 @@
 import static com.scalar.db.storage.dynamo.bytes.BytesUtils.mask;
 
 import com.scalar.db.api.Scan.Ordering.Order;
-import com.scalar.db.io.FloatValue;
+import com.scalar.db.io.FloatColumn;
 import java.nio.ByteBuffer;
 import javax.annotation.concurrent.ThreadSafe;
 
 @ThreadSafe
-public class FloatBytesEncoder implements BytesEncoder<FloatValue> {
+public class FloatBytesEncoder implements BytesEncoder<FloatColumn> {
 
   FloatBytesEncoder() {}
 
   @Override
-  public int encodedLength(FloatValue value, Order order) {
+  public int encodedLength(FloatColumn column, Order order) {
     return 4;
   }
 
   @Override
-  public void encode(FloatValue value, Order order, ByteBuffer dst) {
+  public void encode(FloatColumn column, Order order, ByteBuffer dst) {
+    assert !column.hasNullValue();
     /*
      * The IEE754 floating point format already preserves sort ordering for positive floating point
      * numbers when the raw bytes are compared in most significant byte order.
@@ -30,7 +31,7 @@ public void encode(FloatValue value, Order order, ByteBuffer dst) {
      */
 
     // store the floating point bits into a 32-bit int
-    int i = Float.floatToIntBits(value.getAsFloat());
+    int i = Float.floatToIntBits(column.getFloatValue());
 
     // invert the sign bit and XOR's all other bits with the sign bit itself
     i ^= ((i >> (Integer.SIZE - 1)) | Integer.MIN_VALUE);

core/src/main/java/com/scalar/db/storage/dynamo/bytes/IntBytesEncoder.java

@@ -3,23 +3,25 @@
 import static com.scalar.db.storage.dynamo.bytes.BytesUtils.mask;
 
 import com.scalar.db.api.Scan.Ordering.Order;
-import com.scalar.db.io.IntValue;
+import com.scalar.db.io.IntColumn;
 import java.nio.ByteBuffer;
 import javax.annotation.concurrent.ThreadSafe;
 
 @ThreadSafe
-public class IntBytesEncoder implements BytesEncoder<IntValue> {
+public class IntBytesEncoder implements BytesEncoder<IntColumn> {
 
   IntBytesEncoder() {}
 
   @Override
-  public int encodedLength(IntValue value, Order order) {
+  public int encodedLength(IntColumn column, Order order) {
     return 4;
   }
 
   @Override
-  public void encode(IntValue value, Order order, ByteBuffer dst) {
-    int v = value.getAsInt();
+  public void encode(IntColumn column, Order order, ByteBuffer dst) {
+    assert !column.hasNullValue();
+
+    int v = column.getIntValue();
     dst.put(mask((byte) ((v >> 24) ^ 0x80), order)); // Flip a sign bit to make it binary comparable
     dst.put(mask((byte) (v >> 16), order));
     dst.put(mask((byte) (v >> 8), order));

core/src/main/java/com/scalar/db/storage/dynamo/bytes/KeyBytesEncodedLengthCalculator.java

@@ -1,77 +1,77 @@
 package com.scalar.db.storage.dynamo.bytes;
 
 import com.scalar.db.api.Scan.Ordering.Order;
-import com.scalar.db.io.BigIntValue;
-import com.scalar.db.io.BlobValue;
-import com.scalar.db.io.BooleanValue;
-import com.scalar.db.io.DoubleValue;
-import com.scalar.db.io.FloatValue;
-import com.scalar.db.io.IntValue;
+import com.scalar.db.io.BigIntColumn;
+import com.scalar.db.io.BlobColumn;
+import com.scalar.db.io.BooleanColumn;
+import com.scalar.db.io.Column;
+import com.scalar.db.io.ColumnVisitor;
+import com.scalar.db.io.DoubleColumn;
+import com.scalar.db.io.FloatColumn;
+import com.scalar.db.io.IntColumn;
 import com.scalar.db.io.Key;
-import com.scalar.db.io.TextValue;
-import com.scalar.db.io.Value;
-import com.scalar.db.io.ValueVisitor;
+import com.scalar.db.io.TextColumn;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import java.util.Map;
 import javax.annotation.concurrent.NotThreadSafe;
 
 @NotThreadSafe
-public class KeyBytesEncodedLengthCalculator implements ValueVisitor {
+public class KeyBytesEncodedLengthCalculator implements ColumnVisitor {
 
   private int length;
   private Map<String, Order> keyOrders;
 
   @SuppressFBWarnings("EI_EXPOSE_REP2")
   public int calculate(Key key, Map<String, Order> keyOrders) {
     this.keyOrders = keyOrders;
-    for (Value<?> value : key) {
-      value.accept(this);
+    for (Column<?> column : key.getColumns()) {
+      column.accept(this);
     }
     return length;
   }
 
   @Override
-  public void visit(BooleanValue value) {
+  public void visit(BooleanColumn value) {
     length +=
         BytesEncoders.BOOLEAN.encodedLength(
             value, keyOrders.getOrDefault(value.getName(), Order.ASC));
   }
 
   @Override
-  public void visit(IntValue value) {
+  public void visit(IntColumn value) {
     length +=
         BytesEncoders.INT.encodedLength(value, keyOrders.getOrDefault(value.getName(), Order.ASC));
   }
 
   @Override
-  public void visit(BigIntValue value) {
+  public void visit(BigIntColumn value) {
     length +=
         BytesEncoders.BIGINT.encodedLength(
             value, keyOrders.getOrDefault(value.getName(), Order.ASC));
   }
 
   @Override
-  public void visit(FloatValue value) {
+  public void visit(FloatColumn value) {
     length +=
         BytesEncoders.FLOAT.encodedLength(
             value, keyOrders.getOrDefault(value.getName(), Order.ASC));
   }
 
   @Override
-  public void visit(DoubleValue value) {
+  public void visit(DoubleColumn value) {
     length +=
         BytesEncoders.DOUBLE.encodedLength(
             value, keyOrders.getOrDefault(value.getName(), Order.ASC));
   }
 
   @Override
-  public void visit(TextValue value) {
+  public void visit(TextColumn value) {
     length +=
         BytesEncoders.TEXT.encodedLength(value, keyOrders.getOrDefault(value.getName(), Order.ASC));
   }
 
   @Override
-  public void visit(BlobValue value) {
+  public void visit(BlobColumn value) {
     length +=
         BytesEncoders.BLOB.encodedLength(value, keyOrders.getOrDefault(value.getName(), Order.ASC));
   }