com.datastax.oss.driver.internal.core.type.codec.extras.array.AbstractPrimitiveListToArrayCodec Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.oss.driver.internal.core.type.codec.extras.array;
import com.datastax.oss.driver.api.core.ProtocolVersion;
import com.datastax.oss.driver.api.core.type.ListType;
import com.datastax.oss.driver.api.core.type.reflect.GenericType;
import edu.umd.cs.findbugs.annotations.NonNull;
import edu.umd.cs.findbugs.annotations.Nullable;
import java.lang.reflect.Array;
import java.nio.ByteBuffer;
import java.util.Objects;
/**
* Base class for all codecs dealing with Java primitive arrays. This class provides a more
* efficient implementation of {@link #encode(Object, ProtocolVersion)} and {@link
* #decode(ByteBuffer, ProtocolVersion)} for primitive arrays.
*
* @param The Java primitive array type this codec handles
*/
public abstract class AbstractPrimitiveListToArrayCodec
extends AbstractListToArrayCodec {
/**
* @param cqlType The CQL type. Must be a list type.
* @param javaClass The Java type. Must be an array class.
*/
protected AbstractPrimitiveListToArrayCodec(
@NonNull ListType cqlType, @NonNull GenericType javaClass) {
super(cqlType, javaClass);
GenericType componentType = Objects.requireNonNull(javaClass.getComponentType());
if (!componentType.isPrimitive()) {
throw new IllegalArgumentException(
"Expecting primitive array component type, got " + componentType);
}
}
@Nullable
@Override
public ByteBuffer encode(
@Nullable PrimitiveArrayT array, @NonNull ProtocolVersion protocolVersion) {
if (array == null) {
return null;
}
int length = Array.getLength(array);
int sizeOfElement = 4 + sizeOfComponentType();
int totalSize = 4 + length * sizeOfElement;
ByteBuffer output = ByteBuffer.allocate(totalSize);
output.putInt(length);
for (int i = 0; i < length; i++) {
output.putInt(sizeOfComponentType());
serializeElement(output, array, i, protocolVersion);
}
output.flip();
return output;
}
@Nullable
@Override
public PrimitiveArrayT decode(
@Nullable ByteBuffer bytes, @NonNull ProtocolVersion protocolVersion) {
if (bytes == null || bytes.remaining() == 0) {
return newInstance(0);
}
ByteBuffer input = bytes.duplicate();
int length = input.getInt();
PrimitiveArrayT array = newInstance(length);
for (int i = 0; i < length; i++) {
int elementSize = input.getInt();
// Null elements can happen on the decode path, but we cannot tolerate them
if (elementSize < 0) {
throw new NullPointerException("Primitive arrays cannot store null elements");
} else {
deserializeElement(input, array, i, protocolVersion);
}
}
return array;
}
/**
* Return the size in bytes of the array component type.
*
* @return the size in bytes of the array component type.
*/
protected abstract int sizeOfComponentType();
/**
* Write the {@code index}th element of {@code array} to {@code output}.
*
* @param output The ByteBuffer to write to.
* @param array The array to read from.
* @param index The element index.
* @param protocolVersion The protocol version to use.
*/
protected abstract void serializeElement(
@NonNull ByteBuffer output,
@NonNull PrimitiveArrayT array,
int index,
@NonNull ProtocolVersion protocolVersion);
/**
* Read the {@code index}th element of {@code array} from {@code input}.
*
* @param input The ByteBuffer to read from.
* @param array The array to write to.
* @param index The element index.
* @param protocolVersion The protocol version to use.
*/
protected abstract void deserializeElement(
@NonNull ByteBuffer input,
@NonNull PrimitiveArrayT array,
int index,
@NonNull ProtocolVersion protocolVersion);
}