Type Parameters:: T - The type of elements returned by the iterator. Note that it is strongly recommended to not ever return null; consider using Optional instead of that.

All Superinterfaces:: Iterable<T>

All Known Implementing Classes:: CoreSubsets, DoubleMapIterable, EIEIODataMessage, Machine, ProgressIterable, ReaderLineIterable, Router, TripleMapIterable, VirtualMachine

public interface MappableIterable<T>
extends Iterable<T>

Extends iterable with the ability to be mapped to different values.

Author:: Donal Fellows

Method Summary

Modifier and Type	Method	Description
`default MappableIterable<T>`	`filter(Predicate<T> filterer)`	Apply a filter to an iterable to get another iterable.
`default Optional<T>`	`first()`	Get the first item in the iterable, if there is one.
`default MappableIterable<T>`	`first(int n)`	Get another iterable with the first `n` item in the iterable (or up to that if the source iterable has fewer items).
`default <U> MappableIterable<U>`	`map(Function<T,U> mapper)`	Apply a function to an iterable to get another iterable.
`default Optional<T>`	`nth(int n)`	Index into the iterable.
`default <K, E extends Enum<E>> Map<K,EnumSet<E>>`	`toCollectingMap(Class<E> cls, Function<T,K> keyMapper, Function<T,E> valueMapper)`	Convert this iterable to a map of sets of enum values.
`default <K, V> Map<K,List<V>>`	`toCollectingMap(Function<T,K> keyMapper, Function<T,V> valueMapper)`	Convert this iterable to a map of lists.
`default <K, V, S extends Collection<V>> Map<K,S>`	`toCollectingMap(Supplier<Map<K,S>> mapSupplier, Supplier<S> collectorSupplier, Function<T,K> keyMapper, Function<T,V> valueMapper)`	Convert this iterable to a map of collections.
`default <K, V, S extends Collection<V>> Map<K,S>`	`toCollectingMap(Supplier<S> supplier, Function<T,K> keyMapper, Function<T,V> valueMapper)`	Convert this iterable to a map of collections.
`default List<T>`	`toList()`	Convert this iterable to a list.
`default List<T>`	`toList(Supplier<List<T>> supplier)`	Convert this iterable to a list.
`default <K, V> Map<K,V>`	`toMap(Function<T,K> keyMapper, Function<T,V> valueMapper)`	Convert this iterable to a map.
`default <K, V> Map<K,V>`	`toMap(Supplier<Map<K,V>> supplier, Function<T,K> keyMapper, Function<T,V> valueMapper)`	Convert this iterable to a map.
`default Set<T>`	`toSet()`	Convert this iterable to a set.
`default Set<T>`	`toSet(Supplier<Set<T>> supplier)`	Convert this iterable to a set.

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Method Details
- map
  
  default <U> MappableIterable<U> map(Function<T,U> mapper)
  
  Apply a function to an iterable to get another iterable.
  
  Type Parameters:
  
  U - The type of the elements of the created iterable.
  
  Parameters:
  
  mapper - The function to apply. Should not return null.
  
  Returns:
  
  The new iterable, which may also be mapped.
- filter
  
  default MappableIterable<T> filter(Predicate<T> filterer)
  
  Apply a filter to an iterable to get another iterable. Note that this assumes that null is never produced as a value that should be produced in the resulting iterable.
  
  Parameters:
  
  filterer - The filter function to apply.
  
  Returns:
  
  The new iterable, which only contains elements for which filterer returns true and which are not null.
- first
  
  default Optional<T> first()
  
  Get the first item in the iterable, if there is one.
  
  Returns:
  
  an optional with the first item.
- first
  
  default MappableIterable<T> first(int n)
  
  Get another iterable with the first n item in the iterable (or up to that if the source iterable has fewer items).
  
  Parameters:
  
  n - the maximum number of items of the iterable that are wanted
  
  Returns:
  
  the first n items.
- nth
  
  default Optional<T> nth(int n)
  
  Index into the iterable.
  
  Parameters:
  
  n - The index into the iterable. Zero-based.
  
  Returns:
  
  The item at that index, should it exist.
- toList
  
  default List<T> toList()
  
  Convert this iterable to a list. The order of elements in the list will be the same as the order of items in this iterable.
  
  Returns:
  
  A list of the elements in the iterable. Note that this must be finite! This list is not modifiable.
- toList
  
  default List<T> toList(Supplier<List<T>> supplier)
  
  Convert this iterable to a list. Items will be added to the list in the order of this iterable.
  
  Parameters:
  
  supplier - How to make the list itself.
  
  Returns:
  
  A list of the elements in the iterable. Note that this must be finite! This list is not modifiable.
- toSet
  
  default Set<T> toSet()
  
  Convert this iterable to a set. The natural order of elements in the set will be the same as the order of items in this iterable.
  
  Returns:
  
  A set of the elements in the iterable. Note that this must be finite! This set is not modifiable.
- toSet
  
  default Set<T> toSet(Supplier<Set<T>> supplier)
  
  Convert this iterable to a set. Items will be added to the set in the order of this iterable.
  
  Parameters:
  
  supplier - How to make the set itself.
  
  Returns:
  
  A set of the elements in the iterable. Note that this must be finite! This set is not modifiable.
- toMap
  
  default <K, V> Map<K,V> toMap(Function<T,K> keyMapper, Function<T,V> valueMapper)
  
  Convert this iterable to a map. The natural order of entries will be the same as the natural order of elements in this iterable.
  
  Type Parameters:
  
  K - The type of keys.
  
  V - The type of values.
  
  Parameters:
  
  keyMapper - How to get a key from an element of the iterable.
  
  valueMapper - How to get a value from an element of the iterable.
  
  Returns:
  
  A map derived from elements in the iterable. Note that this must be finite! This map is not modifiable.
- toMap
  
  default <K, V> Map<K,V> toMap(Supplier<Map<K,V>> supplier, Function<T,K> keyMapper, Function<T,V> valueMapper)
  
  Convert this iterable to a map. Items will be added to the map in the order of this iterable.
  
  Type Parameters:
  
  K - The type of keys.
  
  V - The type of values.
  
  Parameters:
  
  supplier - How to make the map itself.
  
  keyMapper - How to get a key from an element of the iterable.
  
  valueMapper - How to get a value from an element of the iterable.
  
  Returns:
  
  A map derived from the elements in the iterable. Note that this must be finite! This map is not modifiable.
- toCollectingMap
  
  default <K, V> Map<K,List<V>> toCollectingMap(Function<T,K> keyMapper, Function<T,V> valueMapper)
  
  Convert this iterable to a map of lists. Items will be added to the map and to the lists in the order of this iterable.
  
  Type Parameters:
  
  K - The type of keys.
  
  V - The type of leaf values.
  
  Parameters:
  
  keyMapper - How to get a key from an element of the iterable.
  
  valueMapper - How to get a leaf value from an element of the iterable.
  
  Returns:
  
  A map derived from the elements in the iterable. Note that this must be finite! This map is not modifiable.
- toCollectingMap
  
  default <K, E extends Enum<E>> Map<K,EnumSet<E>> toCollectingMap(Class<E> cls, Function<T,K> keyMapper, Function<T,E> valueMapper)
  
  Convert this iterable to a map of sets of enum values. Items will be added to the map in the order of this iterable.
  
  Type Parameters:
  
  K - The type of keys.
  
  E - The type of leaf values.
  
  Parameters:
  
  cls - The class of leaf values.
  
  keyMapper - How to get a key from an element of the iterable.
  
  valueMapper - How to get a leaf value from an element of the iterable.
  
  Returns:
  
  A map derived from the elements in the iterable. Note that this must be finite! This map is not modifiable.
- toCollectingMap
  
  default <K, V, S extends Collection<V>> Map<K,S> toCollectingMap(Supplier<S> supplier, Function<T,K> keyMapper, Function<T,V> valueMapper)
  
  Convert this iterable to a map of collections. Items will be added to the map and to the collections in the order of this iterable.
  
  Type Parameters:
  
  K - The type of keys.
  
  V - The type of leaf values.
  
  S - The type of per-key collectors.
  
  Parameters:
  
  supplier - How to make the value collectors.
  
  keyMapper - How to get a key from an element of the iterable.
  
  valueMapper - How to get a leaf value from an element of the iterable.
  
  Returns:
  
  A map derived from the elements in the iterable. Note that this must be finite! This map is not modifiable.
- toCollectingMap
  
  default <K, V, S extends Collection<V>> Map<K,S> toCollectingMap(Supplier<Map<K,S>> mapSupplier, Supplier<S> collectorSupplier, Function<T,K> keyMapper, Function<T,V> valueMapper)
  
  Convert this iterable to a map of collections. Items will be added to the map and to the collections in the order of this iterable.
  
  Type Parameters:
  
  K - The type of keys.
  
  V - The type of leaf values.
  
  S - The type of per-key collectors.
  
  Parameters:
  
  mapSupplier - How to make the map itself.
  
  collectorSupplier - How to make the value collectors.
  
  keyMapper - How to get a key from an element of the iterable.
  
  valueMapper - How to get a value from an element of the iterable.
  
  Returns:
  
  A map derived from the elements in the iterable. Note that this must be finite! This map is not modifiable.

Interface MappableIterable<T>

Method Summary

Methods inherited from interface java.lang.Iterable

Method Details