scala.collection.mutable.CollisionProofHashMap.scala Maven / Gradle / Ivy
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/*
* Scala (https://www.scala-lang.org)
*
* Copyright EPFL and Lightbend, Inc.
*
* Licensed under Apache License 2.0
* (http://www.apache.org/licenses/LICENSE-2.0).
*
* See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*/
package scala.collection
package mutable
import scala.{unchecked => uc}
import scala.annotation.{implicitNotFound, tailrec, unused}
import scala.annotation.unchecked.uncheckedVariance
import scala.collection.generic.DefaultSerializationProxy
import scala.runtime.Statics
/** This class implements mutable maps using a hashtable with red-black trees in the buckets for good
* worst-case performance on hash collisions. An `Ordering` is required for the element type. Equality
* as determined by the `Ordering` has to be consistent with `equals` and `hashCode`. Universal equality
* of numeric types is not supported (similar to `AnyRefMap`).
*
* @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#hash-tables "Scala's Collection Library overview"]]
* section on `Hash Tables` for more information.
*
* @define Coll `mutable.CollisionProofHashMap`
* @define coll mutable collision-proof hash map
* @define mayNotTerminateInf
* @define willNotTerminateInf
*/
final class CollisionProofHashMap[K, V](initialCapacity: Int, loadFactor: Double)(implicit ordering: Ordering[K])
extends AbstractMap[K, V]
with MapOps[K, V, Map, CollisionProofHashMap[K, V]] //--
with StrictOptimizedIterableOps[(K, V), Iterable, CollisionProofHashMap[K, V]]
with StrictOptimizedMapOps[K, V, Map, CollisionProofHashMap[K, V]] { //--
private[this] final def sortedMapFactory: SortedMapFactory[CollisionProofHashMap] = CollisionProofHashMap
def this()(implicit ordering: Ordering[K]) = this(CollisionProofHashMap.defaultInitialCapacity, CollisionProofHashMap.defaultLoadFactor)(ordering)
import CollisionProofHashMap.Node
private[this] type RBNode = CollisionProofHashMap.RBNode[K, V]
private[this] type LLNode = CollisionProofHashMap.LLNode[K, V]
/** The actual hash table. */
private[this] var table: Array[Node] = new Array[Node](tableSizeFor(initialCapacity))
/** The next size value at which to resize (capacity * load factor). */
private[this] var threshold: Int = newThreshold(table.length)
private[this] var contentSize = 0
override def size: Int = contentSize
@`inline` private[this] final def computeHash(o: K): Int = {
val h = if(o.asInstanceOf[AnyRef] eq null) 0 else o.hashCode
h ^ (h >>> 16)
}
@`inline` private[this] final def index(hash: Int) = hash & (table.length - 1)
override protected def fromSpecific(coll: IterableOnce[(K, V)] @uncheckedVariance): CollisionProofHashMap[K, V] @uncheckedVariance = CollisionProofHashMap.from(coll)
override protected def newSpecificBuilder: Builder[(K, V), CollisionProofHashMap[K, V]] @uncheckedVariance = CollisionProofHashMap.newBuilder[K, V]
override def empty: CollisionProofHashMap[K, V] = new CollisionProofHashMap[K, V]
override def contains(key: K): Boolean = findNode(key) ne null
def get(key: K): Option[V] = findNode(key) match {
case null => None
case nd => Some(nd match {
case nd: LLNode @uc => nd.value
case nd: RBNode @uc => nd.value
})
}
@throws[NoSuchElementException]
override def apply(key: K): V = findNode(key) match {
case null => default(key)
case nd => nd match {
case nd: LLNode @uc => nd.value
case nd: RBNode @uc => nd.value
}
}
override def getOrElse[V1 >: V](key: K, default: => V1): V1 = {
val nd = findNode(key)
if (nd eq null) default else nd match {
case nd: LLNode @uc => nd.value
case n => n.asInstanceOf[RBNode].value
}
}
@`inline` private[this] def findNode(elem: K): Node = {
val hash = computeHash(elem)
table(index(hash)) match {
case null => null
case n: LLNode @uc => n.getNode(elem, hash)
case n => n.asInstanceOf[RBNode].getNode(elem, hash)
}
}
override def sizeHint(size: Int): Unit = {
val target = tableSizeFor(((size + 1).toDouble / loadFactor).toInt)
if(target > table.length) {
if(size == 0) reallocTable(target)
else growTable(target)
}
}
override def update(key: K, value: V): Unit = put0(key, value, getOld = false)
override def put(key: K, value: V): Option[V] = put0(key, value, getOld = true) match {
case null => None
case sm => sm
}
def addOne(elem: (K, V)): this.type = { put0(elem._1, elem._2, getOld = false); this }
@`inline` private[this] def put0(key: K, value: V, getOld: Boolean): Some[V] = {
if(contentSize + 1 >= threshold) growTable(table.length * 2)
val hash = computeHash(key)
val idx = index(hash)
put0(key, value, getOld, hash, idx)
}
private[this] def put0(key: K, value: V, getOld: Boolean, hash: Int, idx: Int): Some[V] = {
val res = table(idx) match {
case n: RBNode @uc =>
insert(n, idx, key, hash, value)
case _old =>
val old: LLNode = _old.asInstanceOf[LLNode]
if(old eq null) {
table(idx) = new LLNode(key, hash, value, null)
} else {
var remaining = CollisionProofHashMap.treeifyThreshold
var prev: LLNode = null
var n = old
while((n ne null) && n.hash <= hash && remaining > 0) {
if(n.hash == hash && key == n.key) {
val old = n.value
n.value = value
return (if(getOld) Some(old) else null)
}
prev = n
n = n.next
remaining -= 1
}
if(remaining == 0) {
treeify(old, idx)
return put0(key, value, getOld, hash, idx)
}
if(prev eq null) table(idx) = new LLNode(key, hash, value, old)
else prev.next = new LLNode(key, hash, value, prev.next)
}
true
}
if(res) contentSize += 1
if(res) Some(null.asInstanceOf[V]) else null //TODO
}
private[this] def treeify(old: LLNode, idx: Int): Unit = {
table(idx) = CollisionProofHashMap.leaf(old.key, old.hash, old.value, red = false, null)
var n: LLNode = old.next
while(n ne null) {
val root = table(idx).asInstanceOf[RBNode]
insertIntoExisting(root, idx, n.key, n.hash, n.value, root)
n = n.next
}
}
override def addAll(xs: IterableOnce[(K, V)]): this.type = {
sizeHint(xs, delta = contentSize)
super.addAll(xs)
}
// returns the old value or Statics.pfMarker if not found
private[this] def remove0(elem: K) : Any = {
val hash = computeHash(elem)
val idx = index(hash)
table(idx) match {
case null => Statics.pfMarker
case t: RBNode @uc =>
val v = delete(t, idx, elem, hash)
if(v.asInstanceOf[AnyRef] ne Statics.pfMarker) contentSize -= 1
v
case nd: LLNode @uc if nd.hash == hash && nd.key == elem =>
// first element matches
table(idx) = nd.next
contentSize -= 1
nd.value
case nd: LLNode @uc =>
// find an element that matches
var prev = nd
var next = nd.next
while((next ne null) && next.hash <= hash) {
if(next.hash == hash && next.key == elem) {
prev.next = next.next
contentSize -= 1
return next.value
}
prev = next
next = next.next
}
Statics.pfMarker
}
}
private[this] abstract class MapIterator[R] extends AbstractIterator[R] {
protected[this] def extract(node: LLNode): R
protected[this] def extract(node: RBNode): R
private[this] var i = 0
private[this] var node: Node = null
private[this] val len = table.length
def hasNext: Boolean = {
if(node ne null) true
else {
while(i < len) {
val n = table(i)
i += 1
n match {
case null =>
case n: RBNode @uc =>
node = CollisionProofHashMap.minNodeNonNull(n)
return true
case n: LLNode @uc =>
node = n
return true
}
}
false
}
}
def next(): R =
if(!hasNext) Iterator.empty.next()
else node match {
case n: RBNode @uc =>
val r = extract(n)
node = CollisionProofHashMap.successor(n )
r
case n: LLNode @uc =>
val r = extract(n)
node = n.next
r
}
}
override def keysIterator: Iterator[K] = {
if (isEmpty) Iterator.empty
else new MapIterator[K] {
protected[this] def extract(node: LLNode) = node.key
protected[this] def extract(node: RBNode) = node.key
}
}
override def iterator: Iterator[(K, V)] = {
if (isEmpty) Iterator.empty
else new MapIterator[(K, V)] {
protected[this] def extract(node: LLNode) = (node.key, node.value)
protected[this] def extract(node: RBNode) = (node.key, node.value)
}
}
private[this] def growTable(newlen: Int) = {
var oldlen = table.length
table = java.util.Arrays.copyOf(table, newlen)
threshold = newThreshold(table.length)
while(oldlen < newlen) {
var i = 0
while (i < oldlen) {
val old = table(i)
if(old ne null) splitBucket(old, i, i + oldlen, oldlen)
i += 1
}
oldlen *= 2
}
}
@`inline` private[this] def reallocTable(newlen: Int) = {
table = new Array(newlen)
threshold = newThreshold(table.length)
}
@`inline` private[this] def splitBucket(tree: Node, lowBucket: Int, highBucket: Int, mask: Int): Unit = tree match {
case t: LLNode @uc => splitBucket(t, lowBucket, highBucket, mask)
case t: RBNode @uc => splitBucket(t, lowBucket, highBucket, mask)
}
private[this] def splitBucket(list: LLNode, lowBucket: Int, highBucket: Int, mask: Int): Unit = {
val preLow: LLNode = new LLNode(null.asInstanceOf[K], 0, null.asInstanceOf[V], null)
val preHigh: LLNode = new LLNode(null.asInstanceOf[K], 0, null.asInstanceOf[V], null)
//preLow.next = null
//preHigh.next = null
var lastLow: LLNode = preLow
var lastHigh: LLNode = preHigh
var n = list
while(n ne null) {
val next = n.next
if((n.hash & mask) == 0) { // keep low
lastLow.next = n
lastLow = n
} else { // move to high
lastHigh.next = n
lastHigh = n
}
n = next
}
lastLow.next = null
if(list ne preLow.next) table(lowBucket) = preLow.next
if(preHigh.next ne null) {
table(highBucket) = preHigh.next
lastHigh.next = null
}
}
private[this] def splitBucket(tree: RBNode, lowBucket: Int, highBucket: Int, mask: Int): Unit = {
var lowCount, highCount = 0
tree.foreachNode((n: RBNode) => if((n.hash & mask) != 0) highCount += 1 else lowCount += 1)
if(highCount != 0) {
if(lowCount == 0) {
table(lowBucket) = null
table(highBucket) = tree
} else {
table(lowBucket) = fromNodes(new CollisionProofHashMap.RBNodesIterator(tree).filter(n => (n.hash & mask) == 0), lowCount)
table(highBucket) = fromNodes(new CollisionProofHashMap.RBNodesIterator(tree).filter(n => (n.hash & mask) != 0), highCount)
}
}
}
private[this] def tableSizeFor(capacity: Int) =
(Integer.highestOneBit((capacity-1).max(4))*2).min(1 << 30)
private[this] def newThreshold(size: Int) = (size.toDouble * loadFactor).toInt
override def clear(): Unit = {
java.util.Arrays.fill(table.asInstanceOf[Array[AnyRef]], null)
contentSize = 0
}
override def remove(key: K): Option[V] = {
val v = remove0(key)
if(v.asInstanceOf[AnyRef] eq Statics.pfMarker) None else Some(v.asInstanceOf[V])
}
def subtractOne(elem: K): this.type = { remove0(elem); this }
override def knownSize: Int = size
override def isEmpty: Boolean = size == 0
override def foreach[U](f: ((K, V)) => U): Unit = {
val len = table.length
var i = 0
while(i < len) {
val n = table(i)
if(n ne null) n match {
case n: LLNode @uc => n.foreach(f)
case n: RBNode @uc => n.foreach(f)
}
i += 1
}
}
override def foreachEntry[U](f: (K, V) => U): Unit = {
val len = table.length
var i = 0
while(i < len) {
val n = table(i)
if(n ne null) n match {
case n: LLNode @uc => n.foreachEntry(f)
case n: RBNode @uc => n.foreachEntry(f)
}
i += 1
}
}
protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(new CollisionProofHashMap.DeserializationFactory[K, V](table.length, loadFactor, ordering), this)
override protected[this] def className = "CollisionProofHashMap"
override def getOrElseUpdate(key: K, defaultValue: => V): V = {
val hash = computeHash(key)
val idx = index(hash)
table(idx) match {
case null => ()
case n: LLNode @uc =>
val nd = n.getNode(key, hash)
if(nd != null) return nd.value
case n =>
val nd = n.asInstanceOf[RBNode].getNode(key, hash)
if(nd != null) return nd.value
}
val table0 = table
val default = defaultValue
if(contentSize + 1 >= threshold) growTable(table.length * 2)
// Avoid recomputing index if the `defaultValue()` or new element hasn't triggered a table resize.
val newIdx = if (table0 eq table) idx else index(hash)
put0(key, default, getOld = false, hash, newIdx)
default
}
///////////////////// Overrides code from SortedMapOps
/** Builds a new `CollisionProofHashMap` by applying a function to all elements of this $coll.
*
* @param f the function to apply to each element.
* @return a new $coll resulting from applying the given function
* `f` to each element of this $coll and collecting the results.
*/
def map[K2, V2](f: ((K, V)) => (K2, V2))
(implicit @implicitNotFound(CollisionProofHashMap.ordMsg) ordering: Ordering[K2]): CollisionProofHashMap[K2, V2] =
sortedMapFactory.from(new View.Map[(K, V), (K2, V2)](this, f))
/** Builds a new `CollisionProofHashMap` by applying a function to all elements of this $coll
* and using the elements of the resulting collections.
*
* @param f the function to apply to each element.
* @return a new $coll resulting from applying the given collection-valued function
* `f` to each element of this $coll and concatenating the results.
*/
def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)])
(implicit @implicitNotFound(CollisionProofHashMap.ordMsg) ordering: Ordering[K2]): CollisionProofHashMap[K2, V2] =
sortedMapFactory.from(new View.FlatMap(this, f))
/** Builds a new sorted map by applying a partial function to all elements of this $coll
* on which the function is defined.
*
* @param pf the partial function which filters and maps the $coll.
* @return a new $coll resulting from applying the given partial function
* `pf` to each element on which it is defined and collecting the results.
* The order of the elements is preserved.
*/
def collect[K2, V2](pf: PartialFunction[(K, V), (K2, V2)])
(implicit @implicitNotFound(CollisionProofHashMap.ordMsg) ordering: Ordering[K2]): CollisionProofHashMap[K2, V2] =
sortedMapFactory.from(new View.Collect(this, pf))
override def concat[V2 >: V](suffix: IterableOnce[(K, V2)]): CollisionProofHashMap[K, V2] = sortedMapFactory.from(suffix match {
case it: Iterable[(K, V2)] => new View.Concat(this, it)
case _ => iterator.concat(suffix.iterator)
})
/** Alias for `concat` */
@`inline` override final def ++ [V2 >: V](xs: IterableOnce[(K, V2)]): CollisionProofHashMap[K, V2] = concat(xs)
@deprecated("Consider requiring an immutable Map or fall back to Map.concat", "2.13.0")
override def + [V1 >: V](kv: (K, V1)): CollisionProofHashMap[K, V1] =
sortedMapFactory.from(new View.Appended(this, kv))
@deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0")
override def + [V1 >: V](elem1: (K, V1), elem2: (K, V1), elems: (K, V1)*): CollisionProofHashMap[K, V1] =
sortedMapFactory.from(new View.Concat(new View.Appended(new View.Appended(this, elem1), elem2), elems))
///////////////////// RedBlackTree code derived from mutable.RedBlackTree:
@`inline` private[this] def isRed(node: RBNode) = (node ne null) && node.red
@`inline` private[this] def isBlack(node: RBNode) = (node eq null) || !node.red
@unused @`inline` private[this] def compare(key: K, hash: Int, node: LLNode): Int = {
val i = hash - node.hash
if(i != 0) i else ordering.compare(key, node.key)
}
@`inline` private[this] def compare(key: K, hash: Int, node: RBNode): Int = {
/*val i = hash - node.hash
if(i != 0) i else*/ ordering.compare(key, node.key)
}
// ---- insertion ----
@tailrec private[this] final def insertIntoExisting(_root: RBNode, bucket: Int, key: K, hash: Int, value: V, x: RBNode): Boolean = {
val cmp = compare(key, hash, x)
if(cmp == 0) {
x.value = value
false
} else {
val next = if(cmp < 0) x.left else x.right
if(next eq null) {
val z = CollisionProofHashMap.leaf(key, hash, value, red = true, x)
if (cmp < 0) x.left = z else x.right = z
table(bucket) = fixAfterInsert(_root, z)
return true
}
else insertIntoExisting(_root, bucket, key, hash, value, next)
}
}
private[this] final def insert(tree: RBNode, bucket: Int, key: K, hash: Int, value: V): Boolean = {
if(tree eq null) {
table(bucket) = CollisionProofHashMap.leaf(key, hash, value, red = false, null)
true
} else insertIntoExisting(tree, bucket, key, hash, value, tree)
}
private[this] def fixAfterInsert(_root: RBNode, node: RBNode): RBNode = {
var root = _root
var z = node
while (isRed(z.parent)) {
if (z.parent eq z.parent.parent.left) {
val y = z.parent.parent.right
if (isRed(y)) {
z.parent.red = false
y.red = false
z.parent.parent.red = true
z = z.parent.parent
} else {
if (z eq z.parent.right) {
z = z.parent
root = rotateLeft(root, z)
}
z.parent.red = false
z.parent.parent.red = true
root = rotateRight(root, z.parent.parent)
}
} else { // symmetric cases
val y = z.parent.parent.left
if (isRed(y)) {
z.parent.red = false
y.red = false
z.parent.parent.red = true
z = z.parent.parent
} else {
if (z eq z.parent.left) {
z = z.parent
root = rotateRight(root, z)
}
z.parent.red = false
z.parent.parent.red = true
root = rotateLeft(root, z.parent.parent)
}
}
}
root.red = false
root
}
// ---- deletion ----
// returns the old value or Statics.pfMarker if not found
private[this] def delete(_root: RBNode, bucket: Int, key: K, hash: Int): Any = {
var root = _root
val z = root.getNode(key, hash: Int)
if (z ne null) {
val oldValue = z.value
var y = z
var yIsRed = y.red
var x: RBNode = null
var xParent: RBNode = null
if (z.left eq null) {
x = z.right
root = transplant(root, z, z.right)
xParent = z.parent
}
else if (z.right eq null) {
x = z.left
root = transplant(root, z, z.left)
xParent = z.parent
}
else {
y = CollisionProofHashMap.minNodeNonNull(z.right)
yIsRed = y.red
x = y.right
if (y.parent eq z) xParent = y
else {
xParent = y.parent
root = transplant(root, y, y.right)
y.right = z.right
y.right.parent = y
}
root = transplant(root, z, y)
y.left = z.left
y.left.parent = y
y.red = z.red
}
if (!yIsRed) root = fixAfterDelete(root, x, xParent)
if(root ne _root) table(bucket) = root
oldValue
} else Statics.pfMarker
}
private[this] def fixAfterDelete(_root: RBNode, node: RBNode, parent: RBNode): RBNode = {
var root = _root
var x = node
var xParent = parent
while ((x ne root) && isBlack(x)) {
if (x eq xParent.left) {
var w = xParent.right
// assert(w ne null)
if (w.red) {
w.red = false
xParent.red = true
root = rotateLeft(root, xParent)
w = xParent.right
}
if (isBlack(w.left) && isBlack(w.right)) {
w.red = true
x = xParent
} else {
if (isBlack(w.right)) {
w.left.red = false
w.red = true
root = rotateRight(root, w)
w = xParent.right
}
w.red = xParent.red
xParent.red = false
w.right.red = false
root = rotateLeft(root, xParent)
x = root
}
} else { // symmetric cases
var w = xParent.left
// assert(w ne null)
if (w.red) {
w.red = false
xParent.red = true
root = rotateRight(root, xParent)
w = xParent.left
}
if (isBlack(w.right) && isBlack(w.left)) {
w.red = true
x = xParent
} else {
if (isBlack(w.left)) {
w.right.red = false
w.red = true
root = rotateLeft(root, w)
w = xParent.left
}
w.red = xParent.red
xParent.red = false
w.left.red = false
root = rotateRight(root, xParent)
x = root
}
}
xParent = x.parent
}
if (x ne null) x.red = false
root
}
// ---- helpers ----
@`inline` private[this] def rotateLeft(_root: RBNode, x: RBNode): RBNode = {
var root = _root
val y = x.right
x.right = y.left
val xp = x.parent
if (y.left ne null) y.left.parent = x
y.parent = xp
if (xp eq null) root = y
else if (x eq xp.left) xp.left = y
else xp.right = y
y.left = x
x.parent = y
root
}
@`inline` private[this] def rotateRight(_root: RBNode, x: RBNode): RBNode = {
var root = _root
val y = x.left
x.left = y.right
val xp = x.parent
if (y.right ne null) y.right.parent = x
y.parent = xp
if (xp eq null) root = y
else if (x eq xp.right) xp.right = y
else xp.left = y
y.right = x
x.parent = y
root
}
/**
* Transplant the node `from` to the place of node `to`. This is done by setting `from` as a child of `to`'s previous
* parent and setting `from`'s parent to the `to`'s previous parent. The children of `from` are left unchanged.
*/
private[this] def transplant(_root: RBNode, to: RBNode, from: RBNode): RBNode = {
var root = _root
if (to.parent eq null) root = from
else if (to eq to.parent.left) to.parent.left = from
else to.parent.right = from
if (from ne null) from.parent = to.parent
root
}
// building
def fromNodes(xs: Iterator[Node], size: Int): RBNode = {
val maxUsedDepth = 32 - Integer.numberOfLeadingZeros(size) // maximum depth of non-leaf nodes
def f(level: Int, size: Int): RBNode = size match {
case 0 => null
case 1 =>
val nn = xs.next()
val (key, hash, value) = nn match {
case nn: LLNode @uc => (nn.key, nn.hash, nn.value)
case nn: RBNode @uc => (nn.key, nn.hash, nn.value)
}
new RBNode(key, hash, value, level == maxUsedDepth && level != 1, null, null, null)
case n =>
val leftSize = (size-1)/2
val left = f(level+1, leftSize)
val nn = xs.next()
val right = f(level+1, size-1-leftSize)
val (key, hash, value) = nn match {
case nn: LLNode @uc => (nn.key, nn.hash, nn.value)
case nn: RBNode @uc => (nn.key, nn.hash, nn.value)
}
val n = new RBNode(key, hash, value, red = false, left, right, null)
if(left ne null) left.parent = n
right.parent = n
n
}
f(1, size)
}
}
/**
* $factoryInfo
* @define Coll `mutable.CollisionProofHashMap`
* @define coll mutable collision-proof hash map
*/
@SerialVersionUID(3L)
object CollisionProofHashMap extends SortedMapFactory[CollisionProofHashMap] {
private[collection] final val ordMsg = "No implicit Ordering[${K2}] found to build a CollisionProofHashMap[${K2}, ${V2}]. You may want to upcast to a Map[${K}, ${V}] first by calling `unsorted`."
def from[K : Ordering, V](it: scala.collection.IterableOnce[(K, V)]): CollisionProofHashMap[K, V] = {
val k = it.knownSize
val cap = if(k > 0) ((k + 1).toDouble / defaultLoadFactor).toInt else defaultInitialCapacity
new CollisionProofHashMap[K, V](cap, defaultLoadFactor) ++= it
}
def empty[K : Ordering, V]: CollisionProofHashMap[K, V] = new CollisionProofHashMap[K, V]
def newBuilder[K : Ordering, V]: Builder[(K, V), CollisionProofHashMap[K, V]] = newBuilder(defaultInitialCapacity, defaultLoadFactor)
def newBuilder[K : Ordering, V](initialCapacity: Int, loadFactor: Double): Builder[(K, V), CollisionProofHashMap[K, V]] =
new GrowableBuilder[(K, V), CollisionProofHashMap[K, V]](new CollisionProofHashMap[K, V](initialCapacity, loadFactor)) {
override def sizeHint(size: Int) = elems.sizeHint(size)
}
/** The default load factor for the hash table */
final def defaultLoadFactor: Double = 0.75
/** The default initial capacity for the hash table */
final def defaultInitialCapacity: Int = 16
@SerialVersionUID(3L)
private final class DeserializationFactory[K, V](val tableLength: Int, val loadFactor: Double, val ordering: Ordering[K]) extends Factory[(K, V), CollisionProofHashMap[K, V]] with Serializable {
def fromSpecific(it: IterableOnce[(K, V)]): CollisionProofHashMap[K, V] = new CollisionProofHashMap[K, V](tableLength, loadFactor)(ordering) ++= it
def newBuilder: Builder[(K, V), CollisionProofHashMap[K, V]] = CollisionProofHashMap.newBuilder(tableLength, loadFactor)(using ordering)
}
@unused @`inline` private def compare[K, V](key: K, hash: Int, node: LLNode[K, V])(implicit ord: Ordering[K]): Int = {
val i = hash - node.hash
if(i != 0) i else ord.compare(key, node.key)
}
@`inline` private def compare[K, V](key: K, hash: Int, node: RBNode[K, V])(implicit ord: Ordering[K]): Int = {
/*val i = hash - node.hash
if(i != 0) i else*/ ord.compare(key, node.key)
}
private final val treeifyThreshold = 8
// Superclass for RBNode and LLNode to help the JIT with optimizing instance checks, but no shared common fields.
// Keeping calls monomorphic where possible and dispatching manually where needed is faster.
sealed abstract class Node
/////////////////////////// Red-Black Tree Node
final class RBNode[K, V](var key: K, var hash: Int, var value: V, var red: Boolean, var left: RBNode[K, V], var right: RBNode[K, V], var parent: RBNode[K, V]) extends Node {
override def toString: String = "RBNode(" + key + ", " + hash + ", " + value + ", " + red + ", " + left + ", " + right + ")"
@tailrec def getNode(k: K, h: Int)(implicit ord: Ordering[K]): RBNode[K, V] = {
val cmp = compare(k, h, this)
if (cmp < 0) {
if(left ne null) left.getNode(k, h) else null
} else if (cmp > 0) {
if(right ne null) right.getNode(k, h) else null
} else this
}
def foreach[U](f: ((K, V)) => U): Unit = {
if(left ne null) left.foreach(f)
f((key, value))
if(right ne null) right.foreach(f)
}
def foreachEntry[U](f: (K, V) => U): Unit = {
if(left ne null) left.foreachEntry(f)
f(key, value)
if(right ne null) right.foreachEntry(f)
}
def foreachNode[U](f: RBNode[K, V] => U): Unit = {
if(left ne null) left.foreachNode(f)
f(this)
if(right ne null) right.foreachNode(f)
}
}
@`inline` private def leaf[A, B](key: A, hash: Int, value: B, red: Boolean, parent: RBNode[A, B]): RBNode[A, B] =
new RBNode(key, hash, value, red, null, null, parent)
@tailrec private def minNodeNonNull[A, B](node: RBNode[A, B]): RBNode[A, B] =
if (node.left eq null) node else minNodeNonNull(node.left)
/**
* Returns the node that follows `node` in an in-order tree traversal. If `node` has the maximum key (and is,
* therefore, the last node), this method returns `null`.
*/
private def successor[A, B](node: RBNode[A, B]): RBNode[A, B] = {
if (node.right ne null) minNodeNonNull(node.right)
else {
var x = node
var y = x.parent
while ((y ne null) && (x eq y.right)) {
x = y
y = y.parent
}
y
}
}
private final class RBNodesIterator[A, B](tree: RBNode[A, B])(implicit @unused ord: Ordering[A]) extends AbstractIterator[RBNode[A, B]] {
private[this] var nextNode: RBNode[A, B] = if(tree eq null) null else minNodeNonNull(tree)
def hasNext: Boolean = nextNode ne null
@throws[NoSuchElementException]
def next(): RBNode[A, B] = nextNode match {
case null => Iterator.empty.next()
case node =>
nextNode = successor(node)
node
}
}
/////////////////////////// Linked List Node
private final class LLNode[K, V](var key: K, var hash: Int, var value: V, var next: LLNode[K, V]) extends Node {
override def toString = s"LLNode($key, $value, $hash) -> $next"
private[this] def eq(a: Any, b: Any): Boolean =
if(a.asInstanceOf[AnyRef] eq null) b.asInstanceOf[AnyRef] eq null else a.asInstanceOf[AnyRef].equals(b)
@tailrec def getNode(k: K, h: Int)(implicit ord: Ordering[K]): LLNode[K, V] = {
if(h == hash && eq(k, key) /*ord.compare(k, key) == 0*/) this
else if((next eq null) || (hash > h)) null
else next.getNode(k, h)
}
@tailrec def foreach[U](f: ((K, V)) => U): Unit = {
f((key, value))
if(next ne null) next.foreach(f)
}
@tailrec def foreachEntry[U](f: (K, V) => U): Unit = {
f(key, value)
if(next ne null) next.foreachEntry(f)
}
@tailrec def foreachNode[U](f: LLNode[K, V] => U): Unit = {
f(this)
if(next ne null) next.foreachNode(f)
}
}
}