org.infinispan.commons.util.concurrent.jdk8backported

Class EquivalentConcurrentHashMapV8.Traverser<K,V>

java.lang.Object

org.infinispan.commons.util.concurrent.jdk8backported.EquivalentConcurrentHashMapV8.Traverser<K,V>

Direct Known Subclasses:

EquivalentConcurrentHashMapV8.BaseIterator, EquivalentConcurrentHashMapV8.EntrySpliterator, EquivalentConcurrentHashMapV8.KeySpliterator, EquivalentConcurrentHashMapV8.ValueSpliterator

Enclosing class:

EquivalentConcurrentHashMapV8<K,V>

static class EquivalentConcurrentHashMapV8.Traverser<K,V>
extends java.lang.Object

Encapsulates traversal for methods such as containsValue; also serves as a base class for other iterators and spliterators. Method advance visits once each still-valid node that was reachable upon iterator construction. It might miss some that were added to a bin after the bin was visited, which is OK wrt consistency guarantees. Maintaining this property in the face of possible ongoing resizes requires a fair amount of bookkeeping state that is difficult to optimize away amidst volatile accesses. Even so, traversal maintains reasonable throughput. Normally, iteration proceeds bin-by-bin traversing lists. However, if the table has been resized, then all future steps must traverse both the bin at the current index as well as at (index + baseSize); and so on for further resizings. To paranoically cope with potential sharing by users of iterators across threads, iteration terminates if a bounds checks fails for a table read.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) int	baseIndex
(package private) int	baseLimit
(package private) int	baseSize
(package private) int	index
(package private) EquivalentConcurrentHashMapV8.Node<K,V>	next
(package private) EquivalentConcurrentHashMapV8.TableStack<K,V>	spare
(package private) EquivalentConcurrentHashMapV8.TableStack<K,V>	stack
(package private) EquivalentConcurrentHashMapV8.Node<K,V>[]	tab

Constructor Summary

Constructors

Constructor and Description
EquivalentConcurrentHashMapV8.Traverser(EquivalentConcurrentHashMapV8.Node<K,V>[] tab, int size, int index, int limit)

Method Summary

Methods

Modifier and Type	Method and Description
(package private) EquivalentConcurrentHashMapV8.Node<K,V>	advance() Advances if possible, returning next valid node, or null if none.
private void	pushState(EquivalentConcurrentHashMapV8.Node<K,V>[] t, int i, int n) Saves traversal state upon encountering a forwarding node.
private void	recoverState(int n) Possibly pops traversal state.

Methods inherited from class java.lang.Object

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

Field Detail

tab

EquivalentConcurrentHashMapV8.Node<K,V>[] tab

next

EquivalentConcurrentHashMapV8.Node<K,V> next

stack

EquivalentConcurrentHashMapV8.TableStack<K,V> stack

spare

EquivalentConcurrentHashMapV8.TableStack<K,V> spare

index

int index

baseIndex

int baseIndex

baseLimit

int baseLimit

baseSize

final int baseSize

Constructor Detail

EquivalentConcurrentHashMapV8.Traverser

EquivalentConcurrentHashMapV8.Traverser(EquivalentConcurrentHashMapV8.Node<K,V>[] tab,
                                       int size,
                                       int index,
                                       int limit)

Method Detail

advance

final EquivalentConcurrentHashMapV8.Node<K,V> advance()

Advances if possible, returning next valid node, or null if none.

pushState

private void pushState(EquivalentConcurrentHashMapV8.Node<K,V>[] t,
             int i,
             int n)

Saves traversal state upon encountering a forwarding node.

recoverState

private void recoverState(int n)

Possibly pops traversal state.

Parameters:

n - length of current table