Package io.deephaven.engine.primitive.iterator

Interface CloseableIterator<TYPE>

All Superinterfaces:

AutoCloseable, Iterator<TYPE>

All Known Subinterfaces:

ByteColumnIterator, CharacterColumnIterator, CloseablePrimitiveIterator<TYPE,TYPE_CONSUMER>, CloseablePrimitiveIteratorOfByte, CloseablePrimitiveIteratorOfChar, CloseablePrimitiveIteratorOfDouble, CloseablePrimitiveIteratorOfFloat, CloseablePrimitiveIteratorOfInt, CloseablePrimitiveIteratorOfLong, CloseablePrimitiveIteratorOfShort, ColumnIterator<DATA_TYPE>, DoubleColumnIterator, FloatColumnIterator, IntegerColumnIterator, LongColumnIterator, ObjectColumnIterator<DATA_TYPE>, ShortColumnIterator

All Known Implementing Classes:

ChunkedByteColumnIterator, ChunkedCharacterColumnIterator, ChunkedColumnIterator, ChunkedDoubleColumnIterator, ChunkedFloatColumnIterator, ChunkedIntegerColumnIterator, ChunkedLongColumnIterator, ChunkedObjectColumnIterator, ChunkedShortColumnIterator, SerialByteColumnIterator, SerialCharacterColumnIterator, SerialColumnIterator, SerialDoubleColumnIterator, SerialFloatColumnIterator, SerialIntegerColumnIterator, SerialLongColumnIterator, SerialObjectColumnIterator, SerialShortColumnIterator

public interface CloseableIterator<TYPE>
extends Iterator<TYPE>, AutoCloseable

This interface extends Iterator and AutoCloseable in order to allow for iterators that acquire resources that must be released. Such iterators must document this need, and appropriate measures (e.g. a try-with-resources block) should be taken to ensure that they are closed. Methods that return streams over CloseableIterator instances should ensure that closing the resulting Stream, IntStream, LongStream, or DoubleStream will also close the iterator.

Field Summary

Fields

Modifier and Type	Field	Description
static final CloseableIterator<?>	EMPTY	A re-usable, immutable CloseableIterator with no elements.

Method Summary

Modifier and Type	Method	Description
default void	close()
static <TYPE> CloseableIterator<TYPE>	concat(@NotNull CloseableIterator<TYPE>... subIterators)	Create a CloseableIterator that concatenates an array of non-null subIterators.
static <TYPE> CloseableIterator<TYPE>	empty()	Get a CloseableIterator with no elements.
static <TYPE> CloseableIterator<TYPE>	maybeConcat(@Nullable CloseableIterator<TYPE> first, @Nullable CloseableIterator<TYPE> second, @Nullable CloseableIterator<TYPE> third)	Return a CloseableIterator that concatenates the contents of any non-null CloseableIterator found amongst first, second, and third.
static <TYPE> CloseableIterator<TYPE>	of(@NotNull TYPE... values)	Create a CloseableIterator over an array of int.
static <TYPE> CloseableIterator<TYPE>	repeat(TYPE value, long repeatCount)	Create a CloseableIterator that repeats value, repeatCount times.
default Stream<TYPE>	stream()	Create a Stream over the remaining elements of this CloseableIterator.

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next, remove

Field Details

EMPTY

static final CloseableIterator<?> EMPTY

A re-usable, immutable CloseableIterator with no elements.

Method Details

stream

default Stream<TYPE> stream()

Create a Stream over the remaining elements of this CloseableIterator. Closing the result will close this CloseableIterator.

Returns:

A Stream over the remaining contents of this iterator

close

default void close()

Specified by:

close in interface AutoCloseable

empty

static <TYPE> CloseableIterator<TYPE> empty()

Get a CloseableIterator with no elements. The result does not need to be closed.

Returns:

A CloseableIterator with no elements

of

@SafeVarargs
static <TYPE> CloseableIterator<TYPE> of(@NotNull
 @NotNull TYPE... values)

Create a CloseableIterator over an array of int. The result does not need to be closed.

Parameters:

values - The elements to iterate

Returns:

A CloseableIterator of values

repeat

static <TYPE> CloseableIterator<TYPE> repeat(TYPE value,
 long repeatCount)

Create a CloseableIterator that repeats value, repeatCount times. The result does not need to be closed.

Parameters:

value - The value to repeat

repeatCount - The number of repetitions

Returns:

A CloseableIterator that repeats value, repeatCount times

concat

@SafeVarargs
static <TYPE> CloseableIterator<TYPE> concat(@NotNull
 @NotNull CloseableIterator<TYPE>... subIterators)

Create a CloseableIterator that concatenates an array of non-null subIterators. The result only needs to be closed if any of the subIterators require it.

Parameters:

subIterators - The iterators to concatenate, none of which should be null. If directly passing an array, ensure that this iterator has full ownership.

Returns:

A CloseableIterator concatenating all elements from subIterators

maybeConcat

static <TYPE> CloseableIterator<TYPE> maybeConcat(@Nullable
 @Nullable CloseableIterator<TYPE> first,
 @Nullable
 @Nullable CloseableIterator<TYPE> second,
 @Nullable
 @Nullable CloseableIterator<TYPE> third)

Return a CloseableIterator that concatenates the contents of any non-null CloseableIterator found amongst first, second, and third.

Parameters:

first - The first iterator to consider concatenating

second - The second iterator to consider concatenating

third - The third iterator to consider concatenating

Returns:

A CloseableIterator that concatenates all elements as specified