Package uk.co.terminological.rjava.utils

Class RStreams

java.lang.Object

uk.co.terminological.rjava.utils.RStreams

public class RStreams
extends Object

The Class Java8Streams can be statically imported and allows any type to be flatMapped. e.g. streamOfMaybeListsContainingNullValues.flatMap(l -> maybe(l.getOptionalValue()));

Version:

$Id: $Id

Author:

vp22681

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	RStreams.Exceptional<T>
static interface	RStreams.ExceptionalFunction<T,R>
static class	RStreams.FilteredException

Constructor Summary

Constructors

Constructor	Description
RStreams()

Method Summary

Modifier and Type	Method	Description
static <T, R> Function<T,RStreams.Exceptional<R>>	deferError(RStreams.ExceptionalFunction<T,R> fn)	deferError.
static <T> Stream<T>	maybe(Iterable<T> iter)	Create a stream from a potentially null iterable
static <T> Stream<T>	maybe(Collection<T> list)	Create a stream from a potentially null collection
static <T> Stream<T>	maybe(Iterator<T> iter)	Create a stream from a potentially null iterator
static <T> Stream<T>	maybe(Optional<T> t)	Create a stream from a potentially null optional
static <T> Stream<T>	maybe(Stream<T> stream)	Create a stream from a potentially null stream
static <T> Stream<T>	maybe(T... t)	Create a stream from a potentially null singleton or array
static <T> Stream<T>	maybe(RPrimitive t)	Create a stream from a potentially null or NA valued RPrimitive
static <U extends RPrimitive, T> Stream<T>	maybe(RVector<U> t)	Create a stream from a potentially null or NA valued RVector

Methods inherited from class java.lang.Object

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

Constructor Details

RStreams

public RStreams()

Method Details

maybe

@SafeVarargs
public static <T> Stream<T> maybe(T... t)

Create a stream from a potentially null singleton or array

Type Parameters:

T - any type

Parameters:

t - a set of values

Returns:

a stream

maybe

public static <T> Stream<T> maybe(Collection<T> list)

Create a stream from a potentially null collection

Type Parameters:

T - any type

Parameters:

list - a collection of values

Returns:

a stream

maybe

public static <T> Stream<T> maybe(Stream<T> stream)

Create a stream from a potentially null stream

Type Parameters:

T - any type

Parameters:

stream - a stream

Returns:

a stream

maybe

public static <T> Stream<T> maybe(Optional<T> t)

Create a stream from a potentially null optional

Type Parameters:

T - any type

Parameters:

t - an optional value

Returns:

a stream

maybe

public static <T> Stream<T> maybe(Iterable<T> iter)

Create a stream from a potentially null iterable

Type Parameters:

T - any type

Parameters:

iter - an iterable of values

Returns:

a stream

maybe

public static <T> Stream<T> maybe(Iterator<T> iter)

Create a stream from a potentially null iterator

Type Parameters:

T - any type

Parameters:

iter - an iterator

Returns:

a stream

maybe

public static <T> Stream<T> maybe(RPrimitive t)

Create a stream from a potentially null or NA valued RPrimitive

Type Parameters:

T - any type

Parameters:

t - an RPrimitive

Returns:

a stream of the underlying java object omitting NA values

maybe

public static <U extends RPrimitive,
T> Stream<T> maybe(RVector<U> t)

Create a stream from a potentially null or NA valued RVector

Type Parameters:

T - any type

U - an RPrimitive

Parameters:

t - an RVector of type U

Returns:

a stream of the underlying java object omitting NA values

deferError

public static <T,
R>
Function<T,RStreams.Exceptional<R>> deferError(RStreams.ExceptionalFunction<T,R> fn)

deferError.

Type Parameters:

T - a T class

R - a R class

Parameters:

fn - a RStreams.ExceptionalFunction object

Returns:

a Function object