almost.functional.utils

Class Iterators

java.lang.Object

almost.functional.utils.Iterators

public final class Iterators
extends java.lang.Object

Utility class for Iterators.

Method Summary

Methods

Modifier and Type	Method and Description
static <T> java.util.List<T>	collect(java.util.Iterator<T> iterator) Collect an iterator's elements into a List.
static <T> java.util.Iterator<T>	concat(java.util.Iterator<? extends T>... iterators) Create an iterator which sequentially iterates over a collection of iterators.
static <T> java.util.Iterator<T>	next(java.util.Iterator<? extends T> iterator, int count) This returns an Iterator limited to no more then the next count elements.
static <T> void	parallelBatch(java.util.Iterator<? extends T> iterator, Consumer<java.util.Iterator<? extends T>> consumer, int batchSize) Break an iterator's elements into batches, and invoke the consumer on these batches in a thread pool.

Methods inherited from class java.lang.Object

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

Method Detail

next

public static <T> java.util.Iterator<T> next(java.util.Iterator<? extends T> iterator,
                             int count)

This returns an Iterator limited to no more then the next count elements. The original iterator is advanced by the calls to next on the returned iterator.

Type Parameters:

T - the element type.

Parameters:

iterator - the iterator to draw elements from.

count - the maximum number of elements to draw.

Returns:

An iterator.

Since:

1.9.3

collect

public static <T> java.util.List<T> collect(java.util.Iterator<T> iterator)

Collect an iterator's elements into a List.

Type Parameters:

T - the element type

Parameters:

iterator - the iterator

Returns:

a List containing the elements

Since:

1.9.3

parallelBatch

public static <T> void parallelBatch(java.util.Iterator<? extends T> iterator,
                     Consumer<java.util.Iterator<? extends T>> consumer,
                     int batchSize)
                          throws java.lang.InterruptedException,
                                 java.util.concurrent.ExecutionException

Break an iterator's elements into batches, and invoke the consumer on these batches in a thread pool.

Type Parameters:

T - the element type

Parameters:

iterator - the iterator to draw elements from

consumer - the Consumer to use the batches

batchSize - the maximum number of elements per batch

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

Since:

1.9.3

concat

public static <T> java.util.Iterator<T> concat(java.util.Iterator<? extends T>... iterators)

Create an iterator which sequentially iterates over a collection of iterators.

Type Parameters:

T - the element type

Parameters:

iterators - the iterators to iterate

Returns:

the new iterator