Package org.kiwiproject.collect

Class KiwiStreams

java.lang.Object

org.kiwiproject.collect.KiwiStreams

public final class KiwiStreams
extends Object

Utilities related to Streams that are not already in the JDKs Stream or Guava's Streams.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	KiwiStreams.StreamMode	Describes the type of Stream.

Method Summary

Modifier and Type	Method	Description
static <T> Optional<T>	findFirst(Stream<?> stream, Class<T> typeToFind)	Find the first object having the given typeToFind in a stream of objects.
static <T> Optional<T>	findFirst(Stream<?> stream, Class<T> typeToFind, Predicate<T> predicate)	Find the first object having the given typeToFind and matching the supplied predicate in a stream of objects.
static <T> Stream<T>	stream(Collection<T> collection, KiwiStreams.StreamMode mode)	Return a sequential or parallel Stream over collection based on the given KiwiStreams.StreamMode.

Methods inherited from class java.lang.Object

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

Method Details

findFirst

public static <T> Optional<T> findFirst(Stream<?> stream,
 Class<T> typeToFind)

Find the first object having the given typeToFind in a stream of objects.

Type Parameters:

T - the type token of the type we want to find

Parameters:

stream - the stream of objects of some (unknown) type

typeToFind - the class of the object to find

Returns:

an Optional containing the first object of the given type, or empty

findFirst

public static <T> Optional<T> findFirst(Stream<?> stream,
 Class<T> typeToFind,
 Predicate<T> predicate)

Find the first object having the given typeToFind and matching the supplied predicate in a stream of objects.

Type Parameters:

T - the type token of the type we want to find

Parameters:

stream - the stream of objects of some (unknown) type

typeToFind - the class of the object to find

predicate - the condition that must be satisfied for a match to occur

Returns:

an Optional containing the first object of the given type, or empty

stream

public static <T> Stream<T> stream(Collection<T> collection,
 KiwiStreams.StreamMode mode)

Return a sequential or parallel Stream over collection based on the given KiwiStreams.StreamMode.

Normally you must hard code the type of stream directly in the code using either Collection.stream() or Collection.parallelStream(). This method provides a simple way to determine how to process a stream at runtime, for example based on number of elements or type of algorithm.

Type Parameters:

T - the type of collection elements

Parameters:

collection - the collection to stream

mode - the mode to use when streaming the collection

Returns:

a sequential or parallel Stream over collection