com.datastax.oss.driver.api.core.data

Class CqlVector<T>

java.lang.Object

com.datastax.oss.driver.api.core.data.CqlVector<T>

All Implemented Interfaces:

Serializable, Iterable<T>

public class CqlVector<T>
extends Object
implements Iterable<T>, Serializable

Representation of a vector as defined in CQL.

A CQL vector is a fixed-length array of non-null numeric values. These properties don't map cleanly to an existing class in the standard JDK Collections hierarchy so we provide this value object instead. Like other value object collections returned by the driver instances of this class are not immutable; think of these value objects as a representation of a vector stored in the database as an initial step in some additional computation.

While we don't implement any Collection APIs we do implement Iterable. We also attempt to play nice with the Streams API in order to better facilitate integration with data pipelines. Finally, where possible we've tried to make the API of this class similar to the equivalent methods on List.

See Also:

Serialized Form

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object o)
static <V> CqlVector<V>	from(String str, TypeCodec<V> subtypeCodec) Create a new CqlVector instance from the specified string representation.
T	get(int idx) Retrieve the value at the specified index.
int	hashCode()
boolean	isEmpty() Return a boolean indicating whether the vector is empty.
Iterator<T>	iterator() Create an Iterator for this vector
static <V> CqlVector<V>	newInstance(List<V> list) Create a new CqlVector that "wraps" an existing ArrayList.
static <V> CqlVector<V>	newInstance(V... vals) Create a new CqlVector containing the specified values.
T	set(int idx, T val) Update the value at the specified index.
int	size() Return the size of this vector.
Stream<T>	stream() Create a Stream of the values in this vector
CqlVector<T>	subVector(int from, int to) Return a CqlVector consisting of the contents of a portion of this vector.
String	toString() The string representation of the vector.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

newInstance

public static <V> CqlVector<V> newInstance(V... vals)

Create a new CqlVector containing the specified values.

Parameters:

vals - the collection of values to wrap.

Returns:

a CqlVector wrapping those values

newInstance

public static <V> CqlVector<V> newInstance(List<V> list)

Create a new CqlVector that "wraps" an existing ArrayList. Modifications to the passed ArrayList will also be reflected in the returned CqlVector.

Parameters:

list - the collection of values to wrap.

Returns:

a CqlVector wrapping those values

from

public static <V> CqlVector<V> from(@NonNull
                                    String str,
                                    @NonNull
                                    TypeCodec<V> subtypeCodec)

Create a new CqlVector instance from the specified string representation.

Parameters:

str - a String representation of a CqlVector

subtypeCodec -

Returns:

a new CqlVector built from the String representation

get

public T get(int idx)

Retrieve the value at the specified index. Modelled after List.get(int)

Parameters:

idx - the index to retrieve

Returns:

the value at the specified index

set

public T set(int idx,
             T val)

Update the value at the specified index. Modelled after List.set(int, Object)

Parameters:

idx - the index to set

val - the new value for the specified index

Returns:

the old value for the specified index

size

public int size()

Return the size of this vector. Modelled after List.size()

Returns:

the vector size

subVector

public CqlVector<T> subVector(int from,
                              int to)

Return a CqlVector consisting of the contents of a portion of this vector. Modelled after List.subList(int, int)

Parameters:

from - the index to start from (inclusive)

to - the index to end on (exclusive)

Returns:

a new CqlVector wrapping the sublist

isEmpty

public boolean isEmpty()

Return a boolean indicating whether the vector is empty. Modelled after List.isEmpty()

Returns:

true if the list is empty, false otherwise

iterator

public Iterator<T> iterator()

Create an Iterator for this vector

Specified by:

iterator in interface Iterable<T>

Returns:

the generated iterator

stream

public Stream<T> stream()

Create a Stream of the values in this vector

Returns:

the Stream instance

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

The string representation of the vector. Elements, like strings, may not be properly quoted.

Overrides:

toString in class Object

Returns:

the string representation