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Extended functionality for the Java driver.

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/*
 * Copyright DataStax, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.datastax.driver.extras.codecs.arrays;

import com.datastax.driver.core.DataType;
import com.datastax.driver.core.ProtocolVersion;
import java.nio.ByteBuffer;

/**
 * A codec that maps the CQL type {@code list} to the Java type {@code double[]}.
 *
 * Note that this codec is designed for performance and converts CQL lists directly to
 * {@code double[]}, thus avoiding any unnecessary boxing and unboxing of Java primitive {@code
 * double} values; it also instantiates arrays without the need for an intermediary Java {@code
 * List} object.
 */
public class DoubleArrayCodec extends AbstractPrimitiveArrayCodec {

  public static final DoubleArrayCodec instance = new DoubleArrayCodec();

  public DoubleArrayCodec() {
    super(DataType.list(DataType.cdouble()), double[].class);
  }

  @Override
  protected int sizeOfComponentType() {
    return 8;
  }

  @Override
  protected void serializeElement(
      ByteBuffer output, double[] array, int index, ProtocolVersion protocolVersion) {
    output.putDouble(array[index]);
  }

  @Override
  protected void deserializeElement(
      ByteBuffer input, double[] array, int index, ProtocolVersion protocolVersion) {
    array[index] = input.getDouble();
  }

  @Override
  protected void formatElement(StringBuilder output, double[] array, int index) {
    output.append(array[index]);
  }

  @Override
  protected void parseElement(String input, double[] array, int index) {
    array[index] = Double.parseDouble(input);
  }

  @Override
  protected double[] newInstance(int size) {
    return new double[size];
  }
}