Class ListView<E>
- java.lang.Object
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- one.microstream.collections.ListView<E>
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- All Implemented Interfaces:
Iterable<E>,CapacityCarrying,ExtendedBag<E>,ExtendedCollection<E>,ExtendedList<E>,ExtendedSequence<E>,Sized,XGettingBag<E>,XGettingCollection<E>,XGettingList<E>,XGettingSequence<E>,XIndexIterable<E>,XIterable<E>,XJoinable<E>,Copyable
public class ListView<E> extends Object implements XGettingList<E>
Wrapper class that reduces the services provided by any wrappedXGettingListto only those ofXGettingList, effectively making the wrappedXGettingListinstance immutable (or read-only) if used through an instance of this class.All methods declared in
XGettingListare transparently passed to the wrapped list.
All modifying methods declared inCollectionandList(all variations of add~(), remove~() and retain~() as well as set() and clear()) immediately throw anUnsupportedOperationExceptionwhen called.This concept can be very useful if a class wants to provide public read access to an internal list without either the danger of the list being modified from the outside or the need to copy the whole list on every access.
This is one of many useful concepts that are missing in the JDK Collections Framework and thus so far lead to either inefficient or unneccessary verbose program code (or both).
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Nested Class Summary
Nested Classes Modifier and Type Class Description static classListView.OldListView<E>-
Nested classes/interfaces inherited from interface one.microstream.typing.Copyable
Copyable.Static
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Nested classes/interfaces inherited from interface one.microstream.collections.interfaces.ExtendedCollection
ExtendedCollection.Creator<E,C extends ExtendedCollection<E>>
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Nested classes/interfaces inherited from interface one.microstream.collections.types.XGettingCollection
XGettingCollection.Creator<E>
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Nested classes/interfaces inherited from interface one.microstream.collections.types.XGettingList
XGettingList.Factory<E>
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Nested classes/interfaces inherited from interface one.microstream.collections.types.XIterable
XIterable.Executor<E>
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Constructor Summary
Constructors Constructor Description ListView(XGettingList<E> list)
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Method Summary
Modifier and Type Method Description booleanapplies(Predicate<? super E> predicate)Eat(long index)booleancontains(E element)booleancontainsAll(XGettingCollection<? extends E> elements)booleancontainsId(E element)Special version of contains() that guarantees to use identity comparison (" == ") when searching for the given element regardless of the collection's internal logic.
This method has the same behavior asXGettingCollection.containsSearched(Predicate)with aPredicateimplementation that checks for object identity.booleancontainsSearched(Predicate<? super E> predicate)ListView<E>copy()Creates a true copy of this list which references th same elements in the same order as this list does at the time the method is called.<C extends Consumer<? super E>>
CcopySelection(C target, long... indices)<C extends Consumer<? super E>>
CcopyTo(C target)longcount(E element)longcountBy(Predicate<? super E> predicate)<C extends Consumer<? super E>>
Cdistinct(C target)<C extends Consumer<? super E>>
Cdistinct(C target, Equalator<? super E> equalator)Equalator<? super E>equality()booleanequals(Object o)Deprecated.booleanequals(XGettingCollection<? extends E> samples, Equalator<? super E> equalator)Returnstrueif the passed collection is of the same type as this collection andthis.equalsContent(list, equalator)yieldstrue.booleanequalsContent(XGettingCollection<? extends E> samples, Equalator<? super E> equalator)Returnstrueif all elements of this list and the passed list are sequentially equal as defined by the passed equalator.<C extends Consumer<? super E>>
Cexcept(XGettingCollection<? extends E> other, Equalator<? super E> equalator, C target)<C extends Consumer<? super E>>
CfilterTo(C target, Predicate<? super E> predicate)Efirst()Eget()Gets the first element in the collection.inthashCode()Deprecated.booleanhasVolatileElements()Tells if this collection contains volatile elements.
An element is volatile, if it can become no longer reachable by the collection without being removed from the collection.XImmutableList<E>immure()Provides an instance of an immutable collection type with equal behavior and data as this instance.longindexBy(Predicate<? super E> predicate)longindexOf(E element)<C extends Consumer<? super E>>
Cintersect(XGettingCollection<? extends E> other, Equalator<? super E> equalator, C target)booleanisEmpty()booleanisFull()Returns true if the current capacity cannot be increased any more.booleanisSorted(Comparator<? super E> comparator)<P extends Consumer<? super E>>
Piterate(P procedure)<P extends IndexedAcceptor<? super E>>
PiterateIndexed(P procedure)Iterator<E>iterator()<A> Ajoin(BiConsumer<? super E,? super A> joiner, A aggregate)Elast()longlastIndexBy(Predicate<? super E> predicate)longlastIndexOf(E element)ListIterator<E>listIterator()ListIterator<E>listIterator(long index)Emax(Comparator<? super E> comparator)longmaximumCapacity()Returns the maximum amount of elements this carrier instance can contain.
The actual value may be depend on the configuration of the concrete instance or may depend only on the implementation of the carrier (meaning it is constant for all instances of the implementation, e.g.longmaxIndex(Comparator<? super E> comparator)Emin(Comparator<? super E> comparator)longminIndex(Comparator<? super E> comparator)booleannullAllowed()booleannullContained()ListView.OldListView<E>old()Epeek()Epoll()XGettingList<E>range(long fromIndex, long toIndex)longremainingCapacity()Returns the amount of elements this carrier instance can collect before reaching its maximimum capacity.longscan(Predicate<? super E> predicate)Iterates through the collection and returns the index of the last element that the passedPredicateapplied to ("scanning").Esearch(Predicate<? super E> predicate)Eseek(E sample)Returns the first contained element matching the passed sample as defined by the collection's equality logic or null, if no fitting element is contained.longsize()Object[]toArray()E[]toArray(Class<E> type)ListView<E>toReversed()StringtoString()<C extends Consumer<? super E>>
Cunion(XGettingCollection<? extends E> other, Equalator<? super E> equalator, C target)ListView<E>view()SubListView<E>view(long lowIndex, long highIndex)-
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
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Methods inherited from interface java.lang.Iterable
forEach, spliterator
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Methods inherited from interface one.microstream.collections.types.XGettingCollection
intSize
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Methods inherited from interface one.microstream.collections.types.XGettingSequence
hasIndex
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Constructor Detail
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ListView
public ListView(XGettingList<E> list)
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Method Detail
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immure
public XImmutableList<E> immure()
Description copied from interface:XGettingListProvides an instance of an immutable collection type with equal behavior and data as this instance.If this instance already is of an immutable collection type, it returns itself.
- Specified by:
immurein interfaceXGettingBag<E>- Specified by:
immurein interfaceXGettingCollection<E>- Specified by:
immurein interfaceXGettingList<E>- Specified by:
immurein interfaceXGettingSequence<E>- Returns:
- an immutable copy of this collection instance.
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equality
public Equalator<? super E> equality()
- Specified by:
equalityin interfaceXGettingCollection<E>
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hasVolatileElements
public boolean hasVolatileElements()
Description copied from interface:XGettingCollectionTells if this collection contains volatile elements.
An element is volatile, if it can become no longer reachable by the collection without being removed from the collection. Examples areWeakReferenceofSoftReferenceor implementations of collection entries that remove the element contained in an entry by some means outside the collection.
Note thatWeakReferenceinstances that are added to a a simple (non-volatile) implementation of a collection do NOT make the collection volatile, as the elements themselves (the reference instances) are still strongly referenced.- Specified by:
hasVolatileElementsin interfaceExtendedCollection<E>- Specified by:
hasVolatileElementsin interfaceXGettingCollection<E>- Returns:
trueif the collection contains volatile elements.
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containsSearched
public boolean containsSearched(Predicate<? super E> predicate)
- Specified by:
containsSearchedin interfaceXGettingCollection<E>
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applies
public boolean applies(Predicate<? super E> predicate)
- Specified by:
appliesin interfaceXGettingCollection<E>
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nullAllowed
public boolean nullAllowed()
- Specified by:
nullAllowedin interfaceExtendedCollection<E>
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nullContained
public boolean nullContained()
- Specified by:
nullContainedin interfaceXGettingCollection<E>
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containsAll
public boolean containsAll(XGettingCollection<? extends E> elements)
- Specified by:
containsAllin interfaceXGettingCollection<E>
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contains
public boolean contains(E element)
- Specified by:
containsin interfaceXGettingCollection<E>
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containsId
public boolean containsId(E element)
Description copied from interface:XGettingCollectionSpecial version of contains() that guarantees to use identity comparison (" == ") when searching for the given element regardless of the collection's internal logic.
This method has the same behavior asXGettingCollection.containsSearched(Predicate)with aPredicateimplementation that checks for object identity. The only difference is a performance and usability advantage- Specified by:
containsIdin interfaceXGettingCollection<E>- Parameters:
element- the element to be searched in the collection by identity.- Returns:
- whether this collection contains exactely the given element.
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copy
public ListView<E> copy()
Description copied from interface:XGettingSequenceCreates a true copy of this list which references th same elements in the same order as this list does at the time the method is called. The elements themselves are NOT copied (no deep copying).
The type of the returned list is the same as of this list if possible (i.e.: a SubList can not meaningful return a true copy that references its elements but still is a SubList)- Specified by:
copyin interfaceCopyable- Specified by:
copyin interfaceXGettingBag<E>- Specified by:
copyin interfaceXGettingCollection<E>- Specified by:
copyin interfaceXGettingList<E>- Specified by:
copyin interfaceXGettingSequence<E>- Returns:
- a copy of this list
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filterTo
public <C extends Consumer<? super E>> C filterTo(C target, Predicate<? super E> predicate)
- Specified by:
filterToin interfaceXGettingCollection<E>
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copyTo
public <C extends Consumer<? super E>> C copyTo(C target)
- Specified by:
copyToin interfaceXGettingCollection<E>
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count
public long count(E element)
- Specified by:
countin interfaceXGettingCollection<E>
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countBy
public long countBy(Predicate<? super E> predicate)
- Specified by:
countByin interfaceXGettingCollection<E>
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distinct
public <C extends Consumer<? super E>> C distinct(C target, Equalator<? super E> equalator)
- Specified by:
distinctin interfaceXGettingCollection<E>
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distinct
public <C extends Consumer<? super E>> C distinct(C target)
- Specified by:
distinctin interfaceXGettingCollection<E>
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equals
public boolean equals(XGettingCollection<? extends E> samples, Equalator<? super E> equalator)
Description copied from interface:XGettingCollectionReturnstrueif the passed collection is of the same type as this collection andthis.equalsContent(list, equalator)yieldstrue.- Specified by:
equalsin interfaceXGettingCollection<E>
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equalsContent
public boolean equalsContent(XGettingCollection<? extends E> samples, Equalator<? super E> equalator)
Description copied from interface:XGettingCollectionReturnstrueif all elements of this list and the passed list are sequentially equal as defined by the passed equalator.Note that for colletion types that don't have a defined order of elements, this method is hardly usable (as is
XGettingCollection.equals(Object)for them as defined inCollection). The core problem of comparing collections that have no defined order is that they aren't really reliably comparable to any other collection.- Specified by:
equalsContentin interfaceXGettingCollection<E>equalator- the equalator to use to determine the equality of each element- Returns:
trueif this list is equal to the passed list, false otherwise
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except
public <C extends Consumer<? super E>> C except(XGettingCollection<? extends E> other, Equalator<? super E> equalator, C target)
- Specified by:
exceptin interfaceXGettingCollection<E>
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join
public final <A> A join(BiConsumer<? super E,? super A> joiner, A aggregate)
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iterateIndexed
public final <P extends IndexedAcceptor<? super E>> P iterateIndexed(P procedure)
- Specified by:
iterateIndexedin interfaceXIndexIterable<E>
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get
public E get()
Description copied from interface:XGettingSequenceGets the first element in the collection. This is a parameterless alias vorat(0).first() is an alias for this method for consistency reasons with last().- Specified by:
getin interfaceXGettingCollection<E>- Specified by:
getin interfaceXGettingSequence<E>- Returns:
- the first element.
- See Also:
XGettingSequence.at(long),XGettingSequence.first(),XGettingSequence.last()
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first
public E first()
- Specified by:
firstin interfaceXGettingSequence<E>
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last
public E last()
- Specified by:
lastin interfaceXGettingSequence<E>
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poll
public E poll()
- Specified by:
pollin interfaceXGettingSequence<E>
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peek
public E peek()
- Specified by:
peekin interfaceXGettingSequence<E>
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indexBy
public long indexBy(Predicate<? super E> predicate)
- Specified by:
indexByin interfaceXGettingSequence<E>
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indexOf
public long indexOf(E element)
- Specified by:
indexOfin interfaceXGettingSequence<E>
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intersect
public <C extends Consumer<? super E>> C intersect(XGettingCollection<? extends E> other, Equalator<? super E> equalator, C target)
- Specified by:
intersectin interfaceXGettingCollection<E>
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isSorted
public boolean isSorted(Comparator<? super E> comparator)
- Specified by:
isSortedin interfaceXGettingSequence<E>
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lastIndexBy
public long lastIndexBy(Predicate<? super E> predicate)
- Specified by:
lastIndexByin interfaceXGettingSequence<E>
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lastIndexOf
public long lastIndexOf(E element)
- Specified by:
lastIndexOfin interfaceXGettingSequence<E>
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max
public E max(Comparator<? super E> comparator)
- Specified by:
maxin interfaceXGettingCollection<E>
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maxIndex
public long maxIndex(Comparator<? super E> comparator)
- Specified by:
maxIndexin interfaceXGettingSequence<E>
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min
public E min(Comparator<? super E> comparator)
- Specified by:
minin interfaceXGettingCollection<E>
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minIndex
public long minIndex(Comparator<? super E> comparator)
- Specified by:
minIndexin interfaceXGettingSequence<E>
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scan
public long scan(Predicate<? super E> predicate)
Description copied from interface:XGettingSequenceIterates through the collection and returns the index of the last element that the passedPredicateapplied to ("scanning").- Specified by:
scanin interfaceXGettingSequence<E>- Returns:
- the index of the last positively tested element.
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seek
public E seek(E sample)
Description copied from interface:XGettingCollectionReturns the first contained element matching the passed sample as defined by the collection's equality logic or null, if no fitting element is contained. (For collections using referential equality, this method is basically just a variation ofXGettingCollection.contains(Object)with a different return type. For collections with data-dependant equality, the returned element might be the same as the passed one or a data-wise equal one, depending on the content of the collection)- Specified by:
seekin interfaceXGettingCollection<E>
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search
public E search(Predicate<? super E> predicate)
- Specified by:
searchin interfaceXGettingCollection<E>
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view
public ListView<E> view()
- Specified by:
viewin interfaceXGettingBag<E>- Specified by:
viewin interfaceXGettingCollection<E>- Specified by:
viewin interfaceXGettingList<E>- Specified by:
viewin interfaceXGettingSequence<E>
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view
public SubListView<E> view(long lowIndex, long highIndex)
- Specified by:
viewin interfaceXGettingList<E>- Specified by:
viewin interfaceXGettingSequence<E>
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range
public XGettingList<E> range(long fromIndex, long toIndex)
- Specified by:
rangein interfaceXGettingList<E>- Specified by:
rangein interfaceXGettingSequence<E>
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toReversed
public ListView<E> toReversed()
- Specified by:
toReversedin interfaceXGettingList<E>- Specified by:
toReversedin interfaceXGettingSequence<E>
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union
public <C extends Consumer<? super E>> C union(XGettingCollection<? extends E> other, Equalator<? super E> equalator, C target)
- Specified by:
unionin interfaceXGettingCollection<E>
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copySelection
public <C extends Consumer<? super E>> C copySelection(C target, long... indices)
- Specified by:
copySelectionin interfaceXGettingSequence<E>
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hashCode
@Deprecated public int hashCode()
Deprecated.- Specified by:
hashCodein interfaceXGettingCollection<E>- Overrides:
hashCodein classObject
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equals
@Deprecated public boolean equals(Object o)
Deprecated.Description copied from interface:XGettingCollectionPerforms an equality comparison according to the specification inCollection.Note that it is this interface's author opinion that the whole concept of equals() in standard Java, especially in the collection implementations, is flawed.
The reason is because all different kinds of comparison types that actually depend on the situation have to be mixed up in a harcoded fashion in one method, from identity comparison over data indentity comparison to content comparison.
In order to get the right behavior in every situation, one has to distinct between different types of equality
This means several things:
1.) You can't just say for example an ArrayList is the "same" as a LinkedList just because they contain the same content.
There are different implementations for a good reason, so you have to distinct them when comparing. There are simple code examples which create massive misbehavior that will catastrophically ruin the runtime behavior of a programm due to this error in Java / JDK / Sun / whatever.
2.) You can't always determine equality of two collections by determining equality of each element asCollectiondefines it.As a conclusion: don't use this method!
Be clear what type of comparison you really need, then use one of the following methods and proper comparators:
XGettingCollection.equals(XGettingCollection,Equalator)
XGettingCollection.equalsContent(XGettingCollection,Equalator)
- Specified by:
equalsin interfaceXGettingCollection<E>- Overrides:
equalsin classObject
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at
public E at(long index)
- Specified by:
atin interfaceXGettingSequence<E>
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size
public long size()
- Specified by:
sizein interfaceSized- Specified by:
sizein interfaceXGettingCollection<E>
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maximumCapacity
public long maximumCapacity()
Description copied from interface:CapacityCarryingReturns the maximum amount of elements this carrier instance can contain.
The actual value may be depend on the configuration of the concrete instance or may depend only on the implementation of the carrier (meaning it is constant for all instances of the implementation, e.g.Integer.MAX_VALUE)- Specified by:
maximumCapacityin interfaceCapacityCarrying- Returns:
- the maximum amount of elements this carrier instance can contain.
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isFull
public boolean isFull()
Description copied from interface:CapacityCarryingReturns true if the current capacity cannot be increased any more.- Specified by:
isFullin interfaceCapacityCarrying
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remainingCapacity
public long remainingCapacity()
Description copied from interface:CapacityCarryingReturns the amount of elements this carrier instance can collect before reaching its maximimum capacity.- Specified by:
remainingCapacityin interfaceCapacityCarrying
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toArray
public Object[] toArray()
- Specified by:
toArrayin interfaceXGettingCollection<E>
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listIterator
public ListIterator<E> listIterator()
- Specified by:
listIteratorin interfaceXGettingList<E>
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listIterator
public ListIterator<E> listIterator(long index)
- Specified by:
listIteratorin interfaceXGettingList<E>
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old
public ListView.OldListView<E> old()
- Specified by:
oldin interfaceXGettingCollection<E>- Specified by:
oldin interfaceXGettingList<E>
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