com.datastax.driver.extras.codecs.arrays

Class AbstractPrimitiveArrayCodec<T>

java.lang.Object

com.datastax.driver.core.TypeCodec<T>

com.datastax.driver.extras.codecs.arrays.AbstractArrayCodec<T>

com.datastax.driver.extras.codecs.arrays.AbstractPrimitiveArrayCodec<T>

Type Parameters:

T - The Java primitive array type this codec handles

Direct Known Subclasses:

DoubleArrayCodec, FloatArrayCodec, IntArrayCodec, LongArrayCodec

public abstract class AbstractPrimitiveArrayCodec<T>
extends AbstractArrayCodec<T>

Base class for all codecs dealing with Java primitive arrays. This class provides a more efficient implementation of serialize(Object, ProtocolVersion) and deserialize(ByteBuffer, ProtocolVersion) for primitive arrays.

Nested Class Summary

Nested classes/interfaces inherited from class com.datastax.driver.core.TypeCodec

TypeCodec.AbstractCollectionCodec<E,C extends Collection<E>>, TypeCodec.AbstractMapCodec<K,V>, TypeCodec.AbstractTupleCodec<T>, TypeCodec.AbstractUDTCodec<T>, TypeCodec.PrimitiveBooleanCodec, TypeCodec.PrimitiveByteCodec, TypeCodec.PrimitiveDoubleCodec, TypeCodec.PrimitiveFloatCodec, TypeCodec.PrimitiveIntCodec, TypeCodec.PrimitiveLongCodec, TypeCodec.PrimitiveShortCodec

Field Summary

Fields inherited from class com.datastax.driver.core.TypeCodec

cqlType, javaType

Constructor Summary

Constructors

Constructor and Description
AbstractPrimitiveArrayCodec(DataType.CollectionType cqlType, Class<T> javaClass)

Method Summary

Modifier and Type	Method and Description
T	deserialize(ByteBuffer bytes, ProtocolVersion protocolVersion) Deserialize the given ByteBuffer instance according to the CQL type handled by this codec.
protected abstract void	deserializeElement(ByteBuffer input, T array, int index, ProtocolVersion protocolVersion) Read the indexth element of array from input.
ByteBuffer	serialize(T array, ProtocolVersion protocolVersion) Serialize the given value according to the CQL type handled by this codec.
protected abstract void	serializeElement(ByteBuffer output, T array, int index, ProtocolVersion protocolVersion) Write the indexth element of array to output.
protected abstract int	sizeOfComponentType() Return the size in bytes of the array component type.

Methods inherited from class com.datastax.driver.extras.codecs.arrays.AbstractArrayCodec

format, formatElement, newInstance, parse, parseElement

Methods inherited from class com.datastax.driver.core.TypeCodec

accepts, accepts, accepts, accepts, ascii, bigint, blob, cboolean, cdouble, cfloat, cint, counter, custom, date, decimal, getCqlType, getJavaType, inet, list, map, set, smallInt, time, timestamp, timeUUID, tinyInt, toString, tuple, userType, uuid, varchar, varint

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AbstractPrimitiveArrayCodec

public AbstractPrimitiveArrayCodec(DataType.CollectionType cqlType,
                                   Class<T> javaClass)

Parameters:

cqlType - The CQL type. Must be a list type.

javaClass - The Java type. Must be an array class.

Method Detail

serialize

public ByteBuffer serialize(T array,
                            ProtocolVersion protocolVersion)
                     throws InvalidTypeException

Description copied from class: TypeCodec

Serialize the given value according to the CQL type handled by this codec.

Implementation notes:

1. Null values should be gracefully handled and no exception should be raised; these should be considered as the equivalent of a NULL CQL value;
2. Codecs for CQL collection types should not permit null elements;
3. Codecs for CQL collection types should treat a null input as the equivalent of an empty collection.

Specified by:

serialize in class TypeCodec<T>

Parameters:

array - An instance of T; may be null.

protocolVersion - the protocol version to use when serializing bytes. In most cases, the proper value to provide for this argument is the value returned by ProtocolOptions.getProtocolVersion() (which is the protocol version in use by the driver).

Returns:

A ByteBuffer instance containing the serialized form of T

Throws:

InvalidTypeException - if the given value does not have the expected type

deserialize

public T deserialize(ByteBuffer bytes,
                     ProtocolVersion protocolVersion)
              throws InvalidTypeException

Description copied from class: TypeCodec

Deserialize the given ByteBuffer instance according to the CQL type handled by this codec.

Implementation notes:

1. Null or empty buffers should be gracefully handled and no exception should be raised; these should be considered as the equivalent of a NULL CQL value and, in most cases, should map to null or a default value for the corresponding Java type, if applicable;
2. Codecs for CQL collection types should clearly document whether they return immutable collections or not (note that the driver's default collection codecs return mutable collections);
3. Codecs for CQL collection types should avoid returning null; they should return empty collections instead (the driver's default collection codecs all comply with this rule).
4. The provided ByteBuffer should never be consumed by read operations that modify its current position; if necessary, ByteBuffer.duplicate() duplicate} it before consuming.

Specified by:

deserialize in class TypeCodec<T>

Parameters:

bytes - A ByteBuffer instance containing the serialized form of T; may be null or empty.

protocolVersion - the protocol version to use when serializing bytes. In most cases, the proper value to provide for this argument is the value returned by ProtocolOptions.getProtocolVersion() (which is the protocol version in use by the driver).

Returns:

An instance of T

Throws:

InvalidTypeException - if the given ByteBuffer instance cannot be deserialized

sizeOfComponentType

protected abstract int sizeOfComponentType()

Return the size in bytes of the array component type.

Returns:

the size in bytes of the array component type.

serializeElement

protected abstract void serializeElement(ByteBuffer output,
                                         T array,
                                         int index,
                                         ProtocolVersion protocolVersion)

Write the indexth element of array to output.

Parameters:

output - The ByteBuffer to write to.

array - The array to read from.

index - The element index.

protocolVersion - The protocol version to use.

deserializeElement

protected abstract void deserializeElement(ByteBuffer input,
                                           T array,
                                           int index,
                                           ProtocolVersion protocolVersion)

Read the indexth element of array from input.

Parameters:

input - The ByteBuffer to read from.

array - The array to write to.

index - The element index.

protocolVersion - The protocol version to use.