org.stekikun.dolmen.common

Class Iterables

java.lang.Object

org.stekikun.dolmen.common.Iterables

public abstract class Iterables
extends Object

This class contains various utility methods about Iterables.

Author:

Stéphane Lescuyer

Method Summary

Modifier and Type	Method and Description
static <T> Iterable<T>	concat(Iterable<? extends Iterable<? extends T>> iterables)
static <T> Iterable<T>	concat(Iterable<? extends T>... its)
static <T> Iterable<T>	empty()
static <T,U extends T> Iterable<U>	filterClass(Iterable<T> iterable, Class<? extends U> clazz)
static <T> Iterable<T>	singleton(T elt)
static <T> int	size(Iterable<T> it)
static <T,U> Iterable<U>	transform(Iterable<? extends T> it, Function<? super T,? extends U> f)

Methods inherited from class java.lang.Object

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

Method Detail

empty

public static <T> Iterable<T> empty()

Returns:

the empty iterable

singleton

public static <T> Iterable<T> singleton(T elt)

Parameters:

elt -

Returns:

the iterable containing the single element elt

concat

public static <T> Iterable<T> concat(Iterable<? extends Iterable<? extends T>> iterables)

Parameters:

iterables -

Returns:

an Iterable representing the concatenation of all iterables in iterables, in their relative order

concat

@SafeVarargs
public static <T> Iterable<T> concat(Iterable<? extends T>... its)

Parameters:

its -

Returns:

an Iterable representing the concatenation of all iterables in its, in their relative order

transform

public static <T,U> Iterable<U> transform(Iterable<? extends T> it,
                                          Function<? super T,? extends U> f)

Parameters:

it -

f -

Returns:

a transformed iterable where the function f has been applied to all elements in it

filterClass

public static <T,U extends T> Iterable<U> filterClass(Iterable<T> iterable,
                                                      Class<? extends U> clazz)

Parameters:

iterable -

clazz -

Returns:

the given iterable filtered to only contain elements of the class whose descriptor is clazz

size

public static <T> int size(Iterable<T> it)

Parameters:

it -

Returns:

the number of elements in the iterable it