Stream (Lightweight-Stream-API 1.0.5 API)

java.lang.Object
- com.annimon.stream.Stream<T>

Type Parameters:

T - the type of the stream elements
```
public class Stream<T>
extends Object
```
A sequence of elements supporting aggregate operations.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`allMatch(Predicate<? super T> predicate)` Tests whether all elements match the given predicate.
`boolean`	`anyMatch(Predicate<? super T> predicate)` Tests whether any elements match the given predicate.
`<R,A> R`	`collect(Collector<? super T,A,R> collector)` Collects elements with `collector` that encapsulates supplier, accumulator and combiner functions.
`<R> R`	`collect(Supplier<R> supplier, BiConsumer<R,? super T> accumulator)` Collects elements to `supplier` provided container by applying the given accumulation function.
`static <T> Stream<T>`	`concat(Stream<? extends T> stream1, Stream<? extends T> stream2)` Concatenates two streams.
`long`	`count()` Counts the number of elements in this stream.
`<R> R`	`custom(Function<Stream<T>,R> function)` Applies custom operator on stream.
`Stream<T>`	`distinct()` Returns `Stream` with distinct elements (as determinated by `equals` method).
`Stream<T>`	`filter(Predicate<? super T> predicate)` Returns `Stream` with elements that satisfy the given predicate.
`Optional<T>`	`findFirst()` Returns the first element wrapped by `Optional` class.
`<R> Stream<R>`	`flatMap(Function<? super T,? extends Stream<? extends R>> mapper)` Generates `Stream` by concatenating elements that obtained by applying the given function.
`void`	`forEach(Consumer<? super T> action)` Performs the given action to each element.
`static <T> Stream<T>`	`generate(Supplier<T> supplier)` Creates a `Stream` by elements that generated by `Supplier`.
`Iterator<? extends T>`	`getIterator()` Returns internal stream iterator.
`<K> Stream<Map.Entry<K,List<T>>>`	`groupBy(Function<? super T,? extends K> classifier)` Partitions `Stream` into `Map` entries according to the given classifier function.
`static <T> Stream<T>`	`iterate(T seed, UnaryOperator<T> op)` Creates a `Stream` by applying `UnaryOperator` operation to an initial element `seed`.
`Stream<T>`	`limit(long maxSize)` Returns `Stream` with first `maxSize` elements.
`<R> Stream<R>`	`map(Function<? super T,? extends R> mapper)` Returns `Stream` with elements that obtained by applying the given function.
`Optional<T>`	`max(Comparator<? super T> comparator)` Finds the maximum element according to the given comparator.
`Optional<T>`	`min(Comparator<? super T> comparator)` Finds the minimum element according to the given comparator.
`boolean`	`noneMatch(Predicate<? super T> predicate)` Tests whether no elements match the given predicate.
`static <T> Stream<T>`	`of(Iterable<? extends T> iterable)` Creates a `Stream` from any class that implements `Iterable` interface.
`static <T> Stream<T>`	`of(Iterator<? extends T> iterator)` Creates a `Stream` from any class that implements `Iterator` interface.
`static <T> Stream<T>`	`of(List<? extends T> list)` Creates a `Stream` from `List`.
`static <K,V> Stream<Map.Entry<K,V>>`	`of(Map<K,V> map)` Creates a `Stream` from `Map` entries.
`static <T> Stream<T>`	`of(T... elements)` Creates a `Stream` from the specified values.
`static Stream<Integer>`	`ofRange(int from, int to)` Creates a `Stream<Integer>` from not closed range (from `from` inclusive to `to` exclusive and incremental step `1`).
`static Stream<Long>`	`ofRange(long from, long to)` Creates a `Stream<Long>` from not closed range (from `from` inclusive to `to` exclusive and incremental step `1`).
`static Stream<Integer>`	`ofRangeClosed(int from, int to)` Creates a `Stream<Integer>` from closed range (from `from` inclusive to `to` inclusive and incremental step `1`).
`static Stream<Long>`	`ofRangeClosed(long from, long to)` Creates a `Stream<Long>` from closed range (from `from` inclusive to `to` inclusive and incremental step `1`).
`Stream<T>`	`peek(Consumer<? super T> action)` Perform provided action to each elements.
`Optional<T>`	`reduce(BiFunction<T,T,T> accumulator)` Reduces the elements using provided associative accumulation function.
`T`	`reduce(T identity, BiFunction<T,T,T> accumulator)` Reduces the elements using provided identity value and the associative accumulation function.
`Stream<T>`	`skip(long n)` Skips first `n` elements and returns `Stream` with remaining elements.
`<R extends Comparable> Stream<T>`	`sortBy(Function<? super T,? extends R> f)` Returns `Stream` with sorted elements (as determinated by `Comparable` interface).
`Stream<T>`	`sorted()` Returns `Stream` with sorted elements (as determinated by `Comparable` interface).
`Stream<T>`	`sorted(Comparator<? super T> comparator)` Returns `Stream` with sorted elements (as determinated by provided `Comparator`).

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

- Method Detail
  - of
```
public static <T> Stream<T> of(List<? extends T> list)
```
    Creates a Stream from List.
    
    Type Parameters:
    
    T - the type of the stream elements
    
    Parameters:
    
    list - the list with elements to be passed to stream
    
    Returns:
    
    the new stream
  - of
```
public static <K,V> Stream<Map.Entry<K,V>> of(Map<K,V> map)
```
    Creates a Stream from Map entries.
    
    Type Parameters:
    
    K - the type of map keys
    
    V - the type of map values
    
    Parameters:
    
    map - the map with elements to be passed to stream
    
    Returns:
    
    the new stream
  - of
```
public static <T> Stream<T> of(Iterator<? extends T> iterator)
```
    Creates a Stream from any class that implements Iterator interface.
    
    Type Parameters:
    
    T - the type of the stream elements
    
    Parameters:
    
    iterator - the iterator with elements to be passed to stream
    
    Returns:
    
    the new stream
  - of
```
public static <T> Stream<T> of(Iterable<? extends T> iterable)
```
    Creates a Stream from any class that implements Iterable interface.
    
    Type Parameters:
    
    T - the type of the stream elements
    
    Parameters:
    
    iterable - the iterable with elements to be passed to stream
    
    Returns:
    
    the new stream
  - of
```
public static <T> Stream<T> of(T... elements)
```
    Creates a Stream from the specified values.
    
    Type Parameters:
    
    T - the type of the stream elements
    
    Parameters:
    
    elements - the elements to be passed to stream
    
    Returns:
    
    the new stream
  - ofRange
```
public static Stream<Integer> ofRange(int from,
                                      int to)
```
    Creates a Stream<Integer> from not closed range (from from inclusive to to exclusive and incremental step 1).
    
    Parameters:
    
    from - the initial value (inclusive)
    
    to - the upper bound (exclusive)
    
    Returns:
    
    the new stream
  - ofRange
```
public static Stream<Long> ofRange(long from,
                                   long to)
```
    Creates a Stream<Long> from not closed range (from from inclusive to to exclusive and incremental step 1).
    
    Parameters:
    
    from - the initial value (inclusive)
    
    to - the upper bound (exclusive)
    
    Returns:
    
    the new stream
  - ofRangeClosed
```
public static Stream<Integer> ofRangeClosed(int from,
                                            int to)
```
    Creates a Stream<Integer> from closed range (from from inclusive to to inclusive and incremental step 1).
    
    Parameters:
    
    from - the initial value (inclusive)
    
    to - the upper bound (inclusive)
    
    Returns:
    
    the new stream
  - ofRangeClosed
```
public static Stream<Long> ofRangeClosed(long from,
                                         long to)
```
    Creates a Stream<Long> from closed range (from from inclusive to to inclusive and incremental step 1).
    
    Parameters:
    
    from - the initial value (inclusive)
    
    to - the upper bound (inclusive)
    
    Returns:
    
    the new stream
  - generate
```
public static <T> Stream<T> generate(Supplier<T> supplier)
```
    Creates a Stream by elements that generated by Supplier.
    
    Type Parameters:
    
    T - the type of the stream elements
    
    Parameters:
    
    supplier - the Supplier of generated elements
    
    Returns:
    
    the new stream
  - iterate
```
public static <T> Stream<T> iterate(T seed,
                                    UnaryOperator<T> op)
```
    Creates a Stream by applying UnaryOperator operation to an initial element seed.
    
    Type Parameters:
    
    T - the type of the stream elements
    
    Parameters:
    
    seed - the initial value
    
    op - operator to produce new element by previous one
    
    Returns:
    
    the new stream
  - concat
```
public static <T> Stream<T> concat(Stream<? extends T> stream1,
                                   Stream<? extends T> stream2)
```
    Concatenates two streams.
    
    Type Parameters:
    
    T - The type of stream elements
    
    Parameters:
    
    stream1 - the first stream
    
    stream2 - the second stream
    
    Returns:
    
    the new concatenated stream
  - getIterator
```
public Iterator<? extends T> getIterator()
```
    Returns internal stream iterator.
    
    Returns:
    
    internal stream iterator
  - custom
```
public <R> R custom(Function<Stream<T>,R> function)
```
    Applies custom operator on stream. Transforming function can return Stream for intermediate operations, or any value for terminal operation.
    Operator examples:
```
     // Intermediate operator
     public static class Reverse<T> implements Function<Stream<T>, Stream<T>> {
         @Override
         public Stream<T> apply(Stream<T> stream) {
             final Iterator<? extends T> iterator = stream.getIterator();
             final ArrayDeque<T> deque = new ArrayDeque<T>();
             while (iterator.hasNext()) {
                 deque.addFirst(iterator.next());
             }
             return Stream.of(deque.iterator());
         }
     }
     
     // Intermediate operator based on existing stream operators
     public static class SkipAndLimit<T> implements UnaryOperator<Stream<T>> {
         
         private final int skip, limit;
     
         public SkipAndLimit(int skip, int limit) {
             this.skip = skip;
             this.limit = limit;
         }
         
         @Override
         public Stream<T> apply(Stream<T> stream) {
             return stream.skip(skip).limit(limit);
         }
     }
     
     // Terminal operator
     public static class Sum implements Function<Stream<Integer>, Integer> {
         @Override
         public Integer apply(Stream<Integer> stream) {
             return stream.reduce(0, new BinaryOperator<Integer>() {
                 @Override
                 public Integer apply(Integer value1, Integer value2) {
                     return value1 + value2;
                 }
             });
         }
     }
 
```
    Type Parameters:
    
    R - the type result
    
    Parameters:
    
    function - a transforming function
    
    Returns:
    
    a result of the transforming function
  - filter
```
public Stream<T> filter(Predicate<? super T> predicate)
```
    Returns Stream with elements that satisfy the given predicate.
    This is an intermediate operation.
    
    Parameters:
    
    predicate - the predicate used to filter elements
    
    Returns:
    
    the new stream
  - map
```
public <R> Stream<R> map(Function<? super T,? extends R> mapper)
```
    Returns Stream with elements that obtained by applying the given function.
    This is an intermediate operation.
    
    Type Parameters:
    
    R - the type of elements in resulting stream
    
    Parameters:
    
    mapper - the mapper function used to apply to each element
    
    Returns:
    
    the new stream
  - flatMap
```
public <R> Stream<R> flatMap(Function<? super T,? extends Stream<? extends R>> mapper)
```
    Generates Stream by concatenating elements that obtained by applying the given function.
    This is an intermediate operation.
    
    Type Parameters:
    
    R - the type of elements in resulting stream
    
    Parameters:
    
    mapper - the mapper function used to apply to each element
    
    Returns:
    
    the new stream
  - distinct
```
public Stream<T> distinct()
```
    Returns Stream with distinct elements (as determinated by equals method).
    This is a stateful intermediate operation.
    
    Returns:
    
    the new stream
  - sorted
```
public Stream<T> sorted()
```
    Returns Stream with sorted elements (as determinated by Comparable interface).
    This is a stateful intermediate operation.
    If the elements of this stream are not Comparable, a java.lang.ClassCastException may be thrown when the terminal operation is executed.
    
    Returns:
    
    the new stream
  - sorted
```
public Stream<T> sorted(Comparator<? super T> comparator)
```
    Returns Stream with sorted elements (as determinated by provided Comparator).
    This is a stateful intermediate operation.
    
    Parameters:
    
    comparator - the Comparator to compare elements
    
    Returns:
    
    the new stream
  - sortBy
```
public <R extends Comparable> Stream<T> sortBy(Function<? super T,? extends R> f)
```
    Returns Stream with sorted elements (as determinated by Comparable interface). Each element transformed by given function f before comparing.
    This is a stateful intermediate operation.
    
    Type Parameters:
    
    R - the type of the result of transforming function
    
    Parameters:
    
    f - the transformation function
    
    Returns:
    
    the new stream
  - groupBy
```
public <K> Stream<Map.Entry<K,List<T>>> groupBy(Function<? super T,? extends K> classifier)
```
    Partitions Stream into Map entries according to the given classifier function.
    This is a stateful intermediate operation.
    
    Type Parameters:
    
    K - the type of the keys, which are result of the classifier function
    
    Parameters:
    
    classifier - the classifier function
    
    Returns:
    
    the new stream
  - peek
```
public Stream<T> peek(Consumer<? super T> action)
```
    Perform provided action to each elements.
    This is an intermediate operation.
    
    Parameters:
    
    action - the action to be performed on each element
    
    Returns:
    
    the new stream
  - limit
```
public Stream<T> limit(long maxSize)
```
    Returns Stream with first maxSize elements.
    This is a short-circuiting stateful intermediate operation.
    
    Parameters:
    
    maxSize - the number of elements to limit
    
    Returns:
    
    the new stream
  - skip
```
public Stream<T> skip(long n)
```
    Skips first n elements and returns Stream with remaining elements.
    This is a stateful intermediate operation.
    
    Parameters:
    
    n - the number of elements to skip
    
    Returns:
    
    the new stream
  - forEach
```
public void forEach(Consumer<? super T> action)
```
    Performs the given action to each element.
    This is a terminal operation.
    
    Parameters:
    
    action - the action to be performed on each element
  - reduce
```
public T reduce(T identity,
                BiFunction<T,T,T> accumulator)
```
    Reduces the elements using provided identity value and the associative accumulation function.
    This is a terminal operation.
    
    Parameters:
    
    identity - the initial value
    
    accumulator - the accumulation function
    
    Returns:
    
    the result of the reduction
  - reduce
```
public Optional<T> reduce(BiFunction<T,T,T> accumulator)
```
    Reduces the elements using provided associative accumulation function.
    This is a terminal operation.
    
    Parameters:
    
    accumulator - the accumulation function
    
    Returns:
    
    the result of the reduction
  - collect
```
public <R> R collect(Supplier<R> supplier,
                     BiConsumer<R,? super T> accumulator)
```
    Collects elements to supplier provided container by applying the given accumulation function.
    This is a terminal operation.
    
    Type Parameters:
    
    R - the type of result
    
    Parameters:
    
    supplier - the supplier function that provides container
    
    accumulator - the accumulation function
    
    Returns:
    
    the result of collect elements
    
    See Also:
    
    collect(com.annimon.stream.Collector)
  - collect
```
public <R,A> R collect(Collector<? super T,A,R> collector)
```
    Collects elements with collector that encapsulates supplier, accumulator and combiner functions.
    This is a terminal operation.
    
    Type Parameters:
    
    R - the type of result
    
    A - the intermediate used by Collector
    
    Parameters:
    
    collector - the Collector
    
    Returns:
    
    the result of collect elements
    
    See Also:
    
    collect(com.annimon.stream.function.Supplier, com.annimon.stream.function.BiConsumer)
  - min
```
public Optional<T> min(Comparator<? super T> comparator)
```
    Finds the minimum element according to the given comparator.
    This is a terminal operation.
    
    Parameters:
    
    comparator - the Comparator to compare elements
    
    Returns:
    
    the minimum element
  - max
```
public Optional<T> max(Comparator<? super T> comparator)
```
    Finds the maximum element according to the given comparator.
    This is a terminal operation.
    
    Parameters:
    
    comparator - the Comparator to compare elements
    
    Returns:
    
    the maximum element
  - count
```
public long count()
```
    Counts the number of elements in this stream.
    This is a terminal operation.
    
    Returns:
    
    the count of elements
  - anyMatch
```
public boolean anyMatch(Predicate<? super T> predicate)
```
    Tests whether any elements match the given predicate.
    This is a short-circuiting terminal operation.
    
    Parameters:
    
    predicate - the predicate used to match elements
    
    Returns:
    
    true if any elements match the given predicate, otherwise false
  - allMatch
```
public boolean allMatch(Predicate<? super T> predicate)
```
    Tests whether all elements match the given predicate.
    This is a short-circuiting terminal operation.
    
    Parameters:
    
    predicate - the predicate used to match elements
    
    Returns:
    
    true if all elements match the given predicate, otherwise false
  - noneMatch
```
public boolean noneMatch(Predicate<? super T> predicate)
```
    Tests whether no elements match the given predicate.
    This is a short-circuiting terminal operation.
    
    Parameters:
    
    predicate - the predicate used to match elements
    
    Returns:
    
    true if no elements match the given predicate, otherwise false
  - findFirst
```
public Optional<T> findFirst()
```
    Returns the first element wrapped by Optional class. If stream is empty, returns .
    This is a short-circuiting terminal operation.
    
    Returns:
    
    an Optional with first element or Optional.empty() if stream is empty

Class Stream<T>

Method Summary

Methods inherited from class java.lang.Object

Method Detail

of

of

of

of

of

ofRange

ofRange

ofRangeClosed

ofRangeClosed

generate

iterate

concat

getIterator

custom

filter

map

flatMap

distinct

sorted

sorted

sortBy

groupBy

peek

limit

skip

forEach

reduce

reduce

collect

collect

min

max

count

anyMatch

allMatch

noneMatch

findFirst