StreamLikeIterator (iterator-utils 1.0-SNAPSHOT API)

java.lang.Object
- com.github.robtimus.util.iterator.StreamLikeIterator<E>

Type Parameters:

E - The element type.

All Implemented Interfaces:

Iterator<E>
```
public final class StreamLikeIterator<E>
extends Object
implements Iterator<E>
```
An Iterator that contains additional functionality similar to Stream.

API Note:

Instances of this class support the Iterator.remove() operation if the original iterator does, and no intermediate operation of this class removes support for the operation.

Author:

Rob Spoor

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`allMatch(Predicate<? super E> predicate)` Returns whether or not all elements of this iterator match a specific predicate.
`boolean`	`anyMatch(Predicate<? super E> predicate)` Returns whether or not at least one element of this iterator matches a specific predicate.
`static <E> StreamLikeIterator<E>`	`backedBy(Iterator<E> iterator)` Creates a new `StreamLikeIterator` backed by another iterator.
`<R,A> R`	`collect(Collector<? super E,A,R> collector)` Performs a reduction on the elements of this iterator.
`<R> R`	`collect(Supplier<R> supplier, BiConsumer<R,? super E> accumulator)` Performs a reduction on the elements of this iterator.
`long`	`count()` Returns the number of elements of this iterator.
`StreamLikeIterator<E>`	`distinct()` Returns an iterator that returns the distinct elements of this iterator (according to `Object.equals(Object)`).
`StreamLikeIterator<E>`	`dropWhile(Predicate<? super E> predicate)` Returns an iterator that discards elements of this iterator until an element does not match a specific predicate.
`StreamLikeIterator<E>`	`filter(Predicate<? super E> predicate)` Returns an iterator that filters out elements of this iterator.
`Optional<E>`	`findFirst()` Returns the first element of this iterator.
`<R> StreamLikeIterator<R>`	`flatMap(Function<? super E,? extends Iterator<? extends R>> mapper)` Returns an iterator that replaces the elements of this iterator with the elements of a mapped iterator produced by applying a function to each element.
`void`	`forEachRemaining(Consumer<? super E> action)`
`boolean`	`hasNext()`
`StreamLikeIterator<E>`	`limit(long maxSize)` Returns an iterator that truncates this iterator.
`<R> StreamLikeIterator<R>`	`map(Function<? super E,? extends R> mapper)` Returns an iterator that applies a function to the elements of this iterator.
`Optional<E>`	`max(Comparator<? super E> comparator)` Returns the maximum element of this iterator according to a specific comparator.
`Optional<E>`	`min(Comparator<? super E> comparator)` Returns the minimum element of this iterator according to a specific comparator.
`E`	`next()`
`boolean`	`noneMatch(Predicate<? super E> predicate)` Returns whether or not no element of this iterator matches a specific predicate.
`StreamLikeIterator<E>`	`peek(Consumer<? super E> action)` Returns an iterator that performs an additional action for each element of this iterator.
`Optional<E>`	`reduce(BinaryOperator<E> accumulator)` Performs a reduction on the elements of this iterator.
`E`	`reduce(E identity, BinaryOperator<E> accumulator)` Performs a reduction on the elements of this iterator.
`<U> U`	`reduce(U identity, BiFunction<U,? super E,U> accumulator)` Performs a reduction on the elements of this iterator.
`void`	`remove()`
`StreamLikeIterator<E>`	`skip(long n)` Returns an iterator that discards a number of elements at the start of this iterator.
`StreamLikeIterator<E>`	`takeWhile(Predicate<? super E> predicate)` Returns an iterator that discards elements of this iterator once an element matches a specific predicate.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - hasNext
```
public boolean hasNext()
```
    Specified by:
    
    hasNext in interface Iterator<E>
  - next
```
public E next()
```
    Specified by:
    
    next in interface Iterator<E>
  - remove
```
public void remove()
```
    Specified by:
    
    remove in interface Iterator<E>
  - forEachRemaining
```
public void forEachRemaining(Consumer<? super E> action)
```
    Specified by:
    
    forEachRemaining in interface Iterator<E>
  - filter
```
public StreamLikeIterator<E> filter(Predicate<? super E> predicate)
```
    Returns an iterator that filters out elements of this iterator.
    
    Parameters:
    
    predicate - A predicate that determines whether or not elements should be included.
    
    Returns:
    
    An iterator that filters out elements of this iterator.
    
    Throws:
    
    NullPointerException - If the given predicate is null.
    
    See Also:
    
    Stream.filter(Predicate)
  - map
```
public <R> StreamLikeIterator<R> map(Function<? super E,? extends R> mapper)
```
    Returns an iterator that applies a function to the elements of this iterator.
    
    Type Parameters:
    
    R - The element type of the resulting iterator.
    
    Parameters:
    
    mapper - The function to apply.
    
    Returns:
    
    An iterator that applies the given function to the elements of this iterator.
    
    Throws:
    
    NullPointerException - If the given function is null.
    
    See Also:
    
    Stream.map(Function)
  - flatMap
```
public <R> StreamLikeIterator<R> flatMap(Function<? super E,? extends Iterator<? extends R>> mapper)
```
    Returns an iterator that replaces the elements of this iterator with the elements of a mapped iterator produced by applying a function to each element.
    
    API Note:
    
    Any iterator returned by a method of this interface after this call does not support the Iterator.remove() operation.
    
    Type Parameters:
    
    R - The element type of the resulting iterator.
    
    Parameters:
    
    mapper - The function to apply.
    
    Returns:
    
    An iterator that applies the given function to the elements of this iterator.
    
    Throws:
    
    NullPointerException - If the given function is null.
    
    See Also:
    
    Stream.flatMap(Function)
  - distinct
```
public StreamLikeIterator<E> distinct()
```
    Returns an iterator that returns the distinct elements of this iterator (according to Object.equals(Object)).
    
    API Note:
    
    If elements occur more than once in the original iterator, only the first occurrence will be returned by the returned iterator, and therefore only the first occurrence can be removed.
    
    Returns:
    
    An iterator that returns the distinct elements of this iterator.
    
    See Also:
    
    Stream.distinct()
  - peek
```
public StreamLikeIterator<E> peek(Consumer<? super E> action)
```
    Returns an iterator that performs an additional action for each element of this iterator.
    
    Parameters:
    
    action - The action to perform.
    
    Returns:
    
    An iterator that performs the given action for each element of this iterator.
    
    Throws:
    
    NullPointerException - If the given action is null.
    
    See Also:
    
    Stream.peek(Consumer)
  - limit
```
public StreamLikeIterator<E> limit(long maxSize)
```
    Returns an iterator that truncates this iterator.
    
    Parameters:
    
    maxSize - The maximum number of elements in the returned iterator.
    
    Returns:
    
    An iterator that truncates this iterator.
    
    Throws:
    
    IllegalArgumentException - If the given maximum number of elements is negative.
    
    See Also:
    
    Stream.limit(long)
  - skip
```
public StreamLikeIterator<E> skip(long n)
```
    Returns an iterator that discards a number of elements at the start of this iterator.
    
    Parameters:
    
    n - The number of elements to discard.
    
    Returns:
    
    An iterator that discards the first n elements of this iterator.
    
    Throws:
    
    IllegalArgumentException - If the given number of elements is negative.
    
    See Also:
    
    Stream.skip(long)
  - takeWhile
```
public StreamLikeIterator<E> takeWhile(Predicate<? super E> predicate)
```
    Returns an iterator that discards elements of this iterator once an element matches a specific predicate.
    
    Parameters:
    
    predicate - The predicate that determines when elements are discarded.
    
    Returns:
    
    An iterator that discards elements of this iterator once an element matches the given predicate.
    
    Throws:
    
    NullPointerException - If the given predicate is null.
  - dropWhile
```
public StreamLikeIterator<E> dropWhile(Predicate<? super E> predicate)
```
    Returns an iterator that discards elements of this iterator until an element does not match a specific predicate.
    
    Parameters:
    
    predicate - The predicate that determines until when elements are discarded.
    
    Returns:
    
    An iterator that discards elements of this iterator until an element does not match the given predicate.
    
    Throws:
    
    NullPointerException - If the given predicate is null.
  - reduce
```
public E reduce(E identity,
                BinaryOperator<E> accumulator)
```
    Performs a reduction on the elements of this iterator.
    
    Parameters:
    
    identity - The identity value for the accumulating function.
    
    accumulator - A function for combining two values.
    
    Returns:
    
    The result of the reduction.
    
    Throws:
    
    NullPointerException - If the given accumulator function is null.
    
    See Also:
    
    Stream.reduce(Object, BinaryOperator)
  - reduce
```
public Optional<E> reduce(BinaryOperator<E> accumulator)
```
    Performs a reduction on the elements of this iterator.
    
    Parameters:
    
    accumulator - A function for combining two values.
    
    Returns:
    
    An Optional describing the result of the reduction, or Optional.empty() if this iterator has no elements.
    
    Throws:
    
    NullPointerException - If the given accumulator function or the result of the reduction is null.
    
    See Also:
    
    Stream.reduce(BinaryOperator)
  - reduce
```
public <U> U reduce(U identity,
                    BiFunction<U,? super E,U> accumulator)
```
    Performs a reduction on the elements of this iterator.
    
    Type Parameters:
    
    U - The element type of the resulting iterator.
    
    Parameters:
    
    identity - The identity value for the accumulating function.
    
    accumulator - A function for combining two values.
    
    Returns:
    
    The result of the reduction.
    
    Throws:
    
    NullPointerException - If the given accumulator function is null.
    
    See Also:
    
    Stream.reduce(Object, BiFunction, BinaryOperator)
  - collect
```
public <R> R collect(Supplier<R> supplier,
                     BiConsumer<R,? super E> accumulator)
```
    Performs a reduction on the elements of this iterator.
    
    Type Parameters:
    
    R - The element type of the resulting iterator.
    
    Parameters:
    
    supplier - A supplier for mutable result containers.
    
    accumulator - A function that folds elements into a result container.
    
    Returns:
    
    The result of the reduction.
    
    Throws:
    
    NullPointerException - If the given supplier or accumulator function is null.
    
    See Also:
    
    Stream.collect(Supplier, BiConsumer, BiConsumer)
  - collect
```
public <R,A> R collect(Collector<? super E,A,R> collector)
```
    Performs a reduction on the elements of this iterator.
    
    Type Parameters:
    
    R - The element type of the resulting iterator.
    
    A - The intermediate accumulation type of the collector.
    
    Parameters:
    
    collector - The collector to use for the reduction.
    
    Returns:
    
    The result of the reduction.
    
    Throws:
    
    NullPointerException - If the given collector is null.
    
    See Also:
    
    Stream.collect(Collector)
  - min
```
public Optional<E> min(Comparator<? super E> comparator)
```
    Returns the minimum element of this iterator according to a specific comparator.
    
    Parameters:
    
    comparator - The comparator to use for comparing elements.
    
    Returns:
    
    An Optional describing the minimum element, or Optional.empty() if this iterator has no elements.
    
    Throws:
    
    NullPointerException - If the given comparator is null.
    
    See Also:
    
    Stream.min(Comparator)
  - max
```
public Optional<E> max(Comparator<? super E> comparator)
```
    Returns the maximum element of this iterator according to a specific comparator.
    
    Parameters:
    
    comparator - The comparator to use for comparing elements.
    
    Returns:
    
    An Optional describing the maximum element, or Optional.empty() if this iterator has no elements.
    
    Throws:
    
    NullPointerException - If the given comparator is null.
    
    See Also:
    
    Stream.max(Comparator)
  - count
```
public long count()
```
    Returns the number of elements of this iterator.
    
    Returns:
    
    The number of elements of this iterator.
    
    See Also:
    
    Stream.count()
  - anyMatch
```
public boolean anyMatch(Predicate<? super E> predicate)
```
    Returns whether or not at least one element of this iterator matches a specific predicate.
    
    Parameters:
    
    predicate - The predicate to apply to elements of this iterator.
    
    Returns:
    
    true if at least one element of this iterator matches the given predicate, or false otherwise.
    
    Throws:
    
    NullPointerException - If the given predicate is null.
    
    See Also:
    
    Stream.anyMatch(Predicate)
  - allMatch
```
public boolean allMatch(Predicate<? super E> predicate)
```
    Returns whether or not all elements of this iterator match a specific predicate.
    
    Parameters:
    
    predicate - The predicate to apply to elements of this iterator.
    
    Returns:
    
    true if all elements of this iterator match the given predicate, or false otherwise.
    
    Throws:
    
    NullPointerException - If the given predicate is null.
    
    See Also:
    
    Stream.allMatch(Predicate)
  - noneMatch
```
public boolean noneMatch(Predicate<? super E> predicate)
```
    Returns whether or not no element of this iterator matches a specific predicate.
    
    Parameters:
    
    predicate - The predicate to apply to elements of this iterator.
    
    Returns:
    
    true if no element of this iterator matches the given predicate, or false otherwise.
    
    Throws:
    
    NullPointerException - If the given predicate is null.
    
    See Also:
    
    Stream.noneMatch(Predicate)
  - findFirst
```
public Optional<E> findFirst()
```
    Returns the first element of this iterator.
    
    Returns:
    
    An Optional describing the first element, or Optional.empty() if this iterator has no elements.
    
    See Also:
    
    Stream.findFirst()
  - backedBy
```
public static <E> StreamLikeIterator<E> backedBy(Iterator<E> iterator)
```
    Creates a new StreamLikeIterator backed by another iterator.
    
    Type Parameters:
    
    E - The element type.
    
    Parameters:
    
    iterator - The backing iterator.
    
    Returns:
    
    The created StreamLikeIterator

Class StreamLikeIterator<E>

Method Summary

Methods inherited from class java.lang.Object

Method Detail

hasNext

next

remove

forEachRemaining

filter

map

flatMap

distinct

peek

limit

skip

takeWhile

dropWhile

reduce

reduce

reduce

collect

collect

min

max

count

anyMatch

allMatch

noneMatch

findFirst

backedBy