it.unimi.dsi.fastutil.objects

Class ObjectBigListIterators.AbstractIndexBasedBigIterator<K>

java.lang.Object

it.unimi.dsi.fastutil.objects.AbstractObjectIterator<K>

it.unimi.dsi.fastutil.objects.ObjectBigListIterators.AbstractIndexBasedBigIterator<K>

All Implemented Interfaces:

it.unimi.dsi.fastutil.objects.ObjectIterator<K>, java.util.Iterator<K>

Direct Known Subclasses:

ObjectBigListIterators.AbstractIndexBasedBigListIterator

Enclosing class:

ObjectBigListIterators

public abstract static class ObjectBigListIterators.AbstractIndexBasedBigIterator<K>
extends it.unimi.dsi.fastutil.objects.AbstractObjectIterator<K>

A skeletal implementation for an iterator backed by an index based data store. High performance concrete implementations (like the main Iterator of BigArrayBigList) generally should avoid using this and just implement the interface directly, but should be decent for less performance critical implementations.

As the abstract methods in this class are used in inner loops, it is generally a good idea to override the class as final as to encourage the JVM to inline them (or alternatively, override the abstract methods as final).

Field Summary

Fields

Modifier and Type	Field and Description
protected long	lastReturned The last returned index by a call to next() or, if a list-iterator, {@link java.util.ListIterator#previous().
protected long	minPos The minimum pos can be, and is the logical start of the "range".
protected long	pos The current position index, the index of the item to be returned after the next call to next().

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractIndexBasedBigIterator(long minPos, long initialPos)

Method Summary

Modifier and Type	Method and Description
void	forEachRemaining(java.util.function.Consumer<? super K> action)
protected abstract K	get(long location) Get the item corresponding to the given index location.
protected abstract long	getMaxPos() The maximum pos can be, and is the logical end of the "range".
boolean	hasNext()
K	next()
void	remove()
protected abstract void	remove(long location) Remove the item at the given index.
int	skip(int n)
long	skip(long n)

Methods inherited from class java.lang.Object

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

Field Detail

minPos

protected final long minPos

The minimum pos can be, and is the logical start of the "range". Usually set to the initialPos unless it is a ListIterator, in which case it can vary. There isn't any way for a range to shift its beginning like the end can (through remove(long)), so this is final.

pos

protected long pos

The current position index, the index of the item to be returned after the next call to next().

This value will be between minPos and getMaxPos() (exclusive) (on a best effort, so concurrent structural modifications outside this iterator may cause this to be violated, but that usually invalidates iterators anyways). Thus pos being minPos + 2 would mean next() was called twice and the next call will return the third element of this iterator.

lastReturned

protected long lastReturned

The last returned index by a call to next() or, if a list-iterator, java.util.ListIterator#previous(). Is {@code -1} if no such call has occurred or a mutation has occurred through this iterator and no advancement has been done.

Constructor Detail

AbstractIndexBasedBigIterator

protected AbstractIndexBasedBigIterator(long minPos,
                                        long initialPos)

Method Detail

get

protected abstract K get(long location)

Get the item corresponding to the given index location.

Do not advance pos in this method; the default next method takes care of this.

The location given will be between minPos and getMaxPos() (exclusive). Thus, a location of minPos + 2 would mean next() was called twice and this method should return what the next call to next() should return.

remove

protected abstract void remove(long location)

Remove the item at the given index.

Do not modify pos in this method; the default #remove() method takes care of this.

This method should also do what is needed to track the change to the getMaxPos(). Usually this is accomplished by having this method call the parent Collection's appropriate remove method, and having getMaxPos() track the parent collection's size64().

getMaxPos

protected abstract long getMaxPos()

The maximum pos can be, and is the logical end of the "range".

If pos is equal to the return of this method, this means the last element has been returned and the next call to next() will throw.

Usually set return the parent collection's size64(), but does not have to be (for example, sublists and subranges).

hasNext

public boolean hasNext()

next

public K next()

remove

public void remove()

forEachRemaining

public void forEachRemaining(java.util.function.Consumer<? super K> action)

skip

public long skip(long n)

skip

public int skip(int n)