com.datastax.oss.driver.internal.core.type.codec.extras.vector.AbstractVectorToArrayCodec 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.vector;
import com.datastax.oss.driver.api.core.ProtocolVersion;
import com.datastax.oss.driver.api.core.type.DataType;
import com.datastax.oss.driver.api.core.type.VectorType;
import com.datastax.oss.driver.api.core.type.codec.TypeCodec;
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;
/** Common super-class for all codecs which map a CQL vector type onto a primitive array */
public abstract class AbstractVectorToArrayCodec implements TypeCodec {
@NonNull protected final VectorType cqlType;
@NonNull protected final GenericType javaType;
/**
* @param cqlType The CQL type. Must be a list type.
* @param arrayType The Java type. Must be an array class.
*/
protected AbstractVectorToArrayCodec(
@NonNull VectorType cqlType, @NonNull GenericType arrayType) {
this.cqlType = Objects.requireNonNull(cqlType, "cqlType cannot be null");
this.javaType = Objects.requireNonNull(arrayType, "arrayType cannot be null");
if (!arrayType.isArray()) {
throw new IllegalArgumentException("Expecting Java array class, got " + arrayType);
}
}
@NonNull
@Override
public GenericType getJavaType() {
return this.javaType;
}
@NonNull
@Override
public DataType getCqlType() {
return this.cqlType;
}
@Nullable
@Override
public ByteBuffer encode(@Nullable ArrayT array, @NonNull ProtocolVersion protocolVersion) {
if (array == null) {
return null;
}
int length = Array.getLength(array);
int totalSize = length * sizeOfComponentType();
ByteBuffer output = ByteBuffer.allocate(totalSize);
for (int i = 0; i < length; i++) {
serializeElement(output, array, i, protocolVersion);
}
output.flip();
return output;
}
@Nullable
@Override
public ArrayT decode(@Nullable ByteBuffer bytes, @NonNull ProtocolVersion protocolVersion) {
if (bytes == null || bytes.remaining() == 0) {
throw new IllegalArgumentException(
"Input ByteBuffer must not be null and must have non-zero remaining bytes");
}
ByteBuffer input = bytes.duplicate();
int length = this.cqlType.getDimensions();
int elementSize = sizeOfComponentType();
ArrayT array = newInstance();
for (int i = 0; i < length; i++) {
// 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;
}
/**
* Creates a new array instance with a size matching the specified vector.
*
* @return a new array instance with a size matching the specified vector.
*/
@NonNull
protected abstract ArrayT newInstance();
/**
* 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 ArrayT 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 ArrayT array,
int index,
@NonNull ProtocolVersion protocolVersion);
}