Interface Traversable<E>

All Known Subinterfaces:

IndexedList<E>, Iterable<E>, LinkedList<E>, List<E>, Map<K,V>, Set<E>, SortedMap<K,V>, SortedSet<E>

All Known Implementing Classes:

AbstractIndexedList, AbstractIterable, AbstractLinkedList, AbstractList, AbstractMap, AbstractSet, AbstractSortedMap, AbstractSortedSet, AbstractTraversable, ArrayList, Cons, ConsList, DerivedKeyHashMap, HashMap, HashSet, ListMap, ListMap.Node, MappedIterable, Nil, TreeMap, TreeSet, Vector

public interface Traversable<E>

Traversable is the root of the collection hierarchy.

Traversable allows collections to be defined by a forEach(Function) method and without an iterator. forEach(Function) can be a lot simpler to implement for tree-like structure and also offers a more direct method of traversal for such structures.

Method Summary

Modifier and Type	Method	Description
<U> void	forEach(@NotNull Function<E,U> f)	All collection methods can be built upon this forEach definition.
boolean	isEmpty()	Returns true if this collection is empty.
@NotNull String	makeString(@NotNull String separator)	Returns this collection converted to a string by joining elements together with the specified separator.
@NotNull String	makeString(@NotNull String separator, @NotNull String prefix, @NotNull String postfix, int limit, @NotNull String truncated)	Returns this collection converted to a string.
int	size()	Returns the size of the collection.
<R extends Traversable<E>> R	to(@NotNull Builder<E,R> builder)	Converts this collection to another collection using a builder.
@NotNull Object[]	toArray()	Converts this collection to an array of objects.
E[]	toArray(E[] array)	Converts this collection to an array of objects of the correct type.
@NotNull IndexedList<E>	toIndexedList()	Converts this collection to an indexed list.
@NotNull Set<E>	toSet()	Converts this collection to a set.
@NotNull SortedSet<E>	toSortedSet(Comparator<? super E> comparator)	Converts this collection to a sorted set.

Method Details

forEach

<U> void forEach(@NotNull
 @NotNull Function<E,U> f)

All collection methods can be built upon this forEach definition.

size

int size()

Returns the size of the collection.

Warning: infinite collections are possible, as are collections that require traversal to calculate the size.

isEmpty

boolean isEmpty()

Returns true if this collection is empty.

makeString

@NotNull
@NotNull String makeString(@NotNull
 @NotNull String separator)

Returns this collection converted to a string by joining elements together with the specified separator.

makeString

@NotNull
@NotNull String makeString(@NotNull
 @NotNull String separator,
 @NotNull
 @NotNull String prefix,
 @NotNull
 @NotNull String postfix,
 int limit,
 @NotNull
 @NotNull String truncated)

Returns this collection converted to a string.

Parameters:

separator - Specifies the joining character

prefix - Specifies a prefix to the string

postfix - Species a postfix to the string

limit - Specifies the maximum number of elements to join. If the limit is exceeded, additional elements are ignored.

truncated - If the limit is reached, the truncated value will be appended to indicate the limit was reached.

to

@NotNull
<R extends Traversable<E>> R to(@NotNull
 @NotNull Builder<E,R> builder)

Converts this collection to another collection using a builder.

toSet

@NotNull
@NotNull Set<E> toSet()

Converts this collection to a set.

toSortedSet

@NotNull
@NotNull SortedSet<E> toSortedSet(Comparator<? super E> comparator)

Converts this collection to a sorted set.

toIndexedList

@NotNull
@NotNull IndexedList<E> toIndexedList()

Converts this collection to an indexed list.

toArray

@NotNull
@NotNull Object[] toArray()

Converts this collection to an array of objects.

toArray

@NotNull
E[] toArray(E[] array)

Converts this collection to an array of objects of the correct type.