Package com.db4o.foundation

Class Iterators

java.lang.Object

com.db4o.foundation.Iterators

public class Iterators
extends java.lang.Object

Iterator primitives (concat, map, reduce, filter, etc...).

Field Summary

Fields

Modifier and Type	Field	Description
static Iterable4	EMPTY_ITERABLE
static Iterator4	EMPTY_ITERATOR
static java.lang.Object	SKIP	Constant indicating that the current element in a map(com.db4o.foundation.Iterator4, com.db4o.foundation.Function4) operation should be skipped.

Constructor Summary

Constructors

Constructor	Description
Iterators()

Method Summary

Modifier and Type	Method	Description
static boolean	any(Iterator4 iterator, Predicate4 condition)
static Iterable4	append(Iterable4 front, java.lang.Object last)
static Iterable4	concat(Iterable4 iterables)
static Iterable4	concat(Iterable4... iterables)
static Iterator4	concat(Iterator4 iterators)
static Iterator4	concat(Iterator4... array)
static Iterator4	concat(Iterator4 first, Iterator4 second)
static Iterable4	concatMap(Iterable4 iterable, Function4 function)
static Iterator4	copy(Iterator4 iterator)
static Iterable4	crossProduct(Iterable4 iterables)
static Iterable4	crossProduct(Iterable4... iterables)
static Iterable4	enumerate(Iterable4 iterable)	Generates EnumerateIterator.Tuple items with indexes starting at 0.
static Iterable4	filter(Iterable4 source, Predicate4 predicate)
static Iterator4	filter(Iterator4 iterator, Predicate4 predicate)
static <T> Iterator4<T>	filter(T[] array, Predicate4<T> predicate)
static Iterator4	flatten(Iterator4 iterator)	Yields a flat sequence of elements.
static Iterable4	iterable(Iterator4 iterator)
static <T> Iterable4	iterable(T... objects)
static <T> Iterator4	iterate(List4 list)
static <T> Iterator4	iterate(T... array)
static Iterator4	iterator(Iterable4 iterable)
static <T> Iterator4	iterator(java.util.Collection<T> c)
static java.lang.String	join(Iterable4 i, java.lang.String separator)
static java.lang.String	join(Iterator4 i, java.lang.String separator)
static java.lang.String	join(Iterator4 i, java.lang.String prefix, java.lang.String suffix, java.lang.String separator)
static Iterable4	map(Iterable4 iterable, Function4 function)
static Iterator4	map(Iterator4 iterator, Function4 function)	Returns a new iterator which yields the result of applying the function to every element in the original iterator.
static Iterator4	map(java.lang.Object[] array, Function4 function)
static java.lang.Object	next(Iterator4 iterator)
static <T> java.util.Iterator<T>	platformIterator(Iterator4 iterator)
static Iterator4<java.lang.Integer>	range(int fromInclusive, int toExclusive)
static <T> Iterator4	revert(Iterator4<T> iterator)
static <T> Iterable4<T>	series(T seed, Function4<T,T> function)
static Iterable4	singletonIterable(java.lang.Object element)
static Iterator4	singletonIterator(java.lang.Object element)
static int	size(Iterable4 iterable)
static int	size(Iterator4 iterator)
static <T> Iterator4<T>	take(int count, Iterator4<T> iterator)
static java.lang.Object[]	toArray(Iterator4 tests)
static java.lang.Object[]	toArray(Iterator4 tests, ArrayFactory factory)
static java.lang.String	toString(Iterable4 i)
static java.lang.String	toString(Iterator4 i)

Methods inherited from class java.lang.Object

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

Field Detail

SKIP

public static final java.lang.Object SKIP

Constant indicating that the current element in a map(com.db4o.foundation.Iterator4, com.db4o.foundation.Function4) operation should be skipped.

EMPTY_ITERATOR

public static final Iterator4 EMPTY_ITERATOR

EMPTY_ITERABLE

public static final Iterable4 EMPTY_ITERABLE

Constructor Detail

Iterators

public Iterators()

Method Detail

enumerate

public static Iterable4 enumerate(Iterable4 iterable)

Generates EnumerateIterator.Tuple items with indexes starting at 0.

Parameters:

iterable - the iterable to be enumerated

any

public static boolean any(Iterator4 iterator,
                          Predicate4 condition)

concat

public static Iterator4 concat(Iterator4... array)

concat

public static Iterator4 concat(Iterator4 iterators)

concat

public static Iterable4 concat(Iterable4... iterables)

concat

public static Iterable4 concat(Iterable4 iterables)

concat

public static Iterator4 concat(Iterator4 first,
                               Iterator4 second)

concatMap

public static Iterable4 concatMap(Iterable4 iterable,
                                  Function4 function)

map

public static Iterator4 map(Iterator4 iterator,
                            Function4 function)

Returns a new iterator which yields the result of applying the function to every element in the original iterator. SKIP can be returned from function to indicate the current element should be skipped.

Parameters:

iterator -

function -

Returns:

map

public static Iterator4 map(java.lang.Object[] array,
                            Function4 function)

filter

public static <T> Iterator4<T> filter(T[] array,
                                      Predicate4<T> predicate)

filter

public static Iterable4 filter(Iterable4 source,
                               Predicate4 predicate)

filter

public static Iterator4 filter(Iterator4 iterator,
                               Predicate4 predicate)

singletonIterable

public static Iterable4 singletonIterable(java.lang.Object element)

append

public static Iterable4 append(Iterable4 front,
                               java.lang.Object last)

iterator

public static <T> Iterator4 iterator(java.util.Collection<T> c)

iterator

public static Iterator4 iterator(Iterable4 iterable)

platformIterator

public static <T> java.util.Iterator<T> platformIterator(Iterator4 iterator)

iterate

public static <T> Iterator4 iterate(T... array)

revert

public static <T> Iterator4 revert(Iterator4<T> iterator)

iterate

public static <T> Iterator4 iterate(List4 list)

size

public static int size(Iterable4 iterable)

next

public static java.lang.Object next(Iterator4 iterator)

size

public static int size(Iterator4 iterator)

toString

public static java.lang.String toString(Iterable4 i)

toString

public static java.lang.String toString(Iterator4 i)

join

public static java.lang.String join(Iterable4 i,
                                    java.lang.String separator)

join

public static java.lang.String join(Iterator4 i,
                                    java.lang.String separator)

join

public static java.lang.String join(Iterator4 i,
                                    java.lang.String prefix,
                                    java.lang.String suffix,
                                    java.lang.String separator)

toArray

public static java.lang.Object[] toArray(Iterator4 tests)

toArray

public static java.lang.Object[] toArray(Iterator4 tests,
                                         ArrayFactory factory)

flatten

public static Iterator4 flatten(Iterator4 iterator)

Yields a flat sequence of elements. Any Iterable4 or Iterator4 found in the original sequence is recursively flattened.

Parameters:

iterator - original sequence

map

public static Iterable4 map(Iterable4 iterable,
                            Function4 function)

crossProduct

public static Iterable4 crossProduct(Iterable4 iterables)

crossProduct

public static Iterable4 crossProduct(Iterable4... iterables)

iterable

public static <T> Iterable4 iterable(T... objects)

singletonIterator

public static Iterator4 singletonIterator(java.lang.Object element)

iterable

public static Iterable4 iterable(Iterator4 iterator)

copy

public static Iterator4 copy(Iterator4 iterator)

take

public static <T> Iterator4<T> take(int count,
                                    Iterator4<T> iterator)

range

public static Iterator4<java.lang.Integer> range(int fromInclusive,
                                                 int toExclusive)

series

public static <T> Iterable4<T> series(T seed,
                                      Function4<T,T> function)