package org.aion.util.map;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.AbstractCollection;
import java.util.AbstractSet;
import java.util.Collection;
import java.util.ConcurrentModificationException;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Objects;
import java.util.Set;
import java.util.Spliterator;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.function.Function;
/**
* Don't use this hashmap class without override their hash() function. This class is abstract to
* prevent use it directly.
*
* @author jin
* @param <K>
* @param <V>
*/
public abstract class HashMap<K, V> extends AbstractMap<K, V>
implements Map<K, V>, Cloneable, Serializable {
private static final long serialVersionUID = 362498820763181266L;
/*
* Implementation notes.
*
* This map usually acts as a binned (bucketed) hash table, but
* when bins get too large, they are transformed into bins of
* TreeNodes, each structured similarly to those in
* java.util.TreeMap. Most methods try to use normal bins, but
* relay to TreeNode methods when applicable (simply by checking
* instanceof a node). Bins of TreeNodes may be traversed and
* used like any others, but additionally support faster lookup
* when overpopulated. However, since the vast majority of bins in
* normal use are not overpopulated, checking for existence of
* tree bins may be delayed in the course of table methods.
*
* Tree bins (i.e., bins whose elements are all TreeNodes) are
* ordered primarily by hashCode, but in the case of ties, if two
* elements are of the same "class C implements Comparable<C>",
* type then their compareTo method is used for ordering. (We
* conservatively check generic type via reflection to validate
* this -- see method comparableClassFor). The added complexity
* of tree bins is worthwhile in providing worst-case O(log n)
* operations when keys either have distinct hashes or are
* orderable, Thus, performance degrades gracefully under
* accidental or malicious usages in which hashCode() methods
* return values that are poorly distributed, as well as those in
* which many keys share a hashCode, so long as they are also
* Comparable. (If neither of these apply, we may waste about a
* factor of two in time and space compared to taking no
* precautions. But the only known cases stem from poor user
* programming practices that are already so slow that this makes
* little difference.)
*
* Because TreeNodes are about twice the size of regular nodes, we
* use them only when bins contain enough nodes to warrant use
* (see TREEIFY_THRESHOLD). And when they become too small (due to
* removal or resizing) they are converted back to plain bins. In
* usages with well-distributed user hashCodes, tree bins are
* rarely used. Ideally, under random hashCodes, the frequency of
* nodes in bins follows a Poisson distribution
* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
* parameter of about 0.5 on average for the default resizing
* threshold of 0.75, although with a large variance because of
* resizing granularity. Ignoring variance, the expected
* occurrences of list size k are (exp(-0.5) * pow(0.5, k) /
* factorial(k)). The first values are:
*
* 0: 0.60653066
* 1: 0.30326533
* 2: 0.07581633
* 3: 0.01263606
* 4: 0.00157952
* 5: 0.00015795
* 6: 0.00001316
* 7: 0.00000094
* 8: 0.00000006
* more: less than 1 in ten million
*
* The root of a tree bin is normally its first node. However,
* sometimes (currently only upon Iterator.remove), the root might
* be elsewhere, but can be recovered following parent links
* (method TreeNode.root()).
*
* All applicable internal methods accept a hash code as an
* argument (as normally supplied from a public method), allowing
* them to call each other without recomputing user hashCodes.
* Most internal methods also accept a "tab" argument, that is
* normally the current table, but may be a new or old one when
* resizing or converting.
*
* When bin lists are treeified, split, or untreeified, we keep
* them in the same relative access/traversal order (i.e., field
* Node.next) to better preserve locality, and to slightly
* simplify handling of splits and traversals that invoke
* iterator.remove. When using comparators on insertion, to keep a
* total ordering (or as close as is required here) across
* rebalancings, we compare classes and identityHashCodes as
* tie-breakers.
*
* The use and transitions among plain vs tree modes is
* complicated by the existence of subclass LinkedHashMap. See
* below for hook methods defined to be invoked upon insertion,
* removal and access that allow LinkedHashMap internals to
* otherwise remain independent of these mechanics. (This also
* requires that a map instance be passed to some utility methods
* that may create new nodes.)
*
* The concurrent-programming-like SSA-based coding style helps
* avoid aliasing errors amid all of the twisty pointer operations.
*/
/** The default initial capacity - MUST be a power of two. */
static final int DEFAULT_INITIAL_CAPACITY = 1 << 4; // aka 16
/**
* The maximum capacity, used if a higher value is implicitly specified by either of the
* constructors with arguments. MUST be a power of two <= 1<<30.
*/
static final int MAXIMUM_CAPACITY = 1 << 30;
/** The load factor used when none specified in constructor. */
static final float DEFAULT_LOAD_FACTOR = 0.75f;
/**
* The bin count threshold for using a tree rather than list for a bin. Bins are converted to
* trees when adding an element to a bin with at least this many nodes. The value must be
* greater than 2 and should be at least 8 to mesh with assumptions in tree removal about
* conversion back to plain bins upon shrinkage.
*/
static final int TREEIFY_THRESHOLD = 8;
/**
* The bin count threshold for untreeifying a (split) bin during a resize operation. Should be
* less than TREEIFY_THRESHOLD, and at most 6 to mesh with shrinkage detection under removal.
*/
static final int UNTREEIFY_THRESHOLD = 6;
/**
* The smallest table capacity for which bins may be treeified. (Otherwise the table is resized
* if too many nodes in a bin.) Should be at least 4 * TREEIFY_THRESHOLD to avoid conflicts
* between resizing and treeification thresholds.
*/
static final int MIN_TREEIFY_CAPACITY = 64;
/**
* Basic hash bin node, used for most entries. (See below for TreeNode subclass, and in
* LinkedHashMap for its Entry subclass.)
*/
static class Node<K, V> implements Map.Entry<K, V> {
final int hash;
protected final K key;
V value;
Node<K, V> next;
Node(int hash, K key, V value, Node<K, V> next) {
this.hash = hash;
this.key = key;
this.value = value;
this.next = next;
}
public final K getKey() {
return key;
}
public final V getValue() {
return value;
}
public final String toString() {
return key + "=" + value;
}
public final int hashCode() {
return Objects.hashCode(key) ^ Objects.hashCode(value);
}
public final V setValue(V newValue) {
V oldValue = value;
value = newValue;
return oldValue;
}
public boolean equals(Object o) {
if (o == this) {
return true;
}
if (o instanceof Map.Entry) {
Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
if (Objects.equals(key, e.getKey()) && Objects.equals(value, e.getValue())) {
return true;
}
}
return false;
}
}
/* ---------------- Static utilities -------------- */
/**
* Computes key.hashCode() and spreads (XORs) higher bits of hash to lower. Because the table
* uses power-of-two masking, sets of hashes that vary only in bits above the current mask will
* always collide. (Among known examples are sets of Float keys holding consecutive whole
* numbers in small tables.) So we apply a transform that spreads the impact of higher bits
* downward. There is a tradeoff between speed, utility, and quality of bit-spreading. Because
* many common sets of hashes are already reasonably distributed (so don't benefit from
* spreading), and because we use trees to handle large sets of collisions in bins, we just XOR
* some shifted bits in the cheapest possible way to reduce systematic lossage, as well as to
* incorporate impact of the highest bits that would otherwise never be used in index
* calculations because of table bounds.
*/
protected abstract int hash(Object key);
// static int hash(Object key) {
// int h;
// return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);
// }
protected abstract boolean keyEquals(Object key, K k);
protected abstract boolean valEquals(Object value, V v);
/** Returns x's Class if it is of the form "class C implements Comparable<C>", else null. */
static Class<?> comparableClassFor(Object x) {
if (x instanceof Comparable) {
Class<?> c;
Type[] ts, as;
ParameterizedType p;
if ((c = x.getClass()) == String.class) // bypass checks
{
return c;
}
if ((ts = c.getGenericInterfaces()) != null) {
for (Type t : ts) {
if ((t instanceof ParameterizedType)
&& ((p = (ParameterizedType) t).getRawType() == Comparable.class)
&& (as = p.getActualTypeArguments()) != null
&& as.length == 1
&& as[0] == c) // type arg is c
{
return c;
}
}
}
}
return null;
}
/** Returns k.compareTo(x) if x matches kc (k's screened comparable class), else 0. */
@SuppressWarnings({"rawtypes", "unchecked"}) // for cast to Comparable
static int compareComparables(Class<?> kc, Object k, Object x) {
return (x == null || x.getClass() != kc ? 0 : ((Comparable) k).compareTo(x));
}
/** Returns a power of two size for the given target capacity. */
static final int tableSizeFor(int cap) {
int n = cap - 1;
n |= n >>> 1;
n |= n >>> 2;
n |= n >>> 4;
n |= n >>> 8;
n |= n >>> 16;
return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
}
/* ---------------- Fields -------------- */
/**
* The table, initialized on first use, and resized as necessary. When allocated, length is
* always a power of two. (We also tolerate length zero in some operations to allow
* bootstrapping mechanics that are currently not needed.)
*/
transient Node<K, V>[] table;
/** Holds cached entrySet(). Note that AbstractMap fields are used for keySet() and values(). */
transient Set<Map.Entry<K, V>> entrySet;
/** The number of key-value mappings contained in this map. */
transient int size;
/**
* The number of times this HashMap has been structurally modified Structural modifications are
* those that change the number of mappings in the HashMap or otherwise modify its internal
* structure (e.g., rehash). This field is used to make iterators on Collection-views of the
* HashMap fail-fast. (See ConcurrentModificationException).
*/
transient int modCount;
/**
* The next size value at which to resize (capacity * load factor).
*
* @serial
*/
// (The javadoc description is true upon serialization.
// Additionally, if the table array has not been allocated, this
// field holds the initial array capacity, or zero signifying
// DEFAULT_INITIAL_CAPACITY.)
int threshold;
/**
* The load factor for the hash table.
*
* @serial
*/
final float loadFactor;
/* ---------------- Public operations -------------- */
/**
* Constructs an empty {@code HashMap} with the specified initial capacity and load factor.
*
* @param initialCapacity the initial capacity
* @param loadFactor the load factor
* @throws IllegalArgumentException if the initial capacity is negative or the load factor is
* nonpositive
*/
public HashMap(int initialCapacity, float loadFactor) {
if (initialCapacity < 0) {
throw new IllegalArgumentException("Illegal initial capacity: " + initialCapacity);
}
if (initialCapacity > MAXIMUM_CAPACITY) {
initialCapacity = MAXIMUM_CAPACITY;
}
if (loadFactor <= 0 || Float.isNaN(loadFactor)) {
throw new IllegalArgumentException("Illegal load factor: " + loadFactor);
}
this.loadFactor = loadFactor;
this.threshold = tableSizeFor(initialCapacity);
}
/**
* Constructs an empty {@code HashMap} with the specified initial capacity and the default load
* factor (0.75).
*
* @param initialCapacity the initial capacity.
* @throws IllegalArgumentException if the initial capacity is negative.
*/
public HashMap(int initialCapacity) {
this(initialCapacity, DEFAULT_LOAD_FACTOR);
}
/**
* Constructs an empty {@code HashMap} with the default initial capacity (16) and the default
* load factor (0.75).
*/
public HashMap() {
this.loadFactor = DEFAULT_LOAD_FACTOR; // all other fields defaulted
}
/**
* Constructs a new {@code HashMap} with the same mappings as the specified {@code Map}. The
* {@code HashMap} is created with default load factor (0.75) and an initial capacity sufficient
* to hold the mappings in the specified {@code Map}.
*
* @param m the map whose mappings are to be placed in this map
* @throws NullPointerException if the specified map is null
*/
public HashMap(Map<? extends K, ? extends V> m) {
this.loadFactor = DEFAULT_LOAD_FACTOR;
putMapEntries(m, false);
}
/**
* Implements Map.putAll and Map constructor
*
* @param m the map
* @param evict false when initially constructing this map, else true (relayed to method
* afterNodeInsertion).
*/
final void putMapEntries(Map<? extends K, ? extends V> m, boolean evict) {
int s = m.size();
if (s > 0) {
if (table == null) { // pre-size
float ft = ((float) s / loadFactor) + 1.0F;
int t = ((ft < (float) MAXIMUM_CAPACITY) ? (int) ft : MAXIMUM_CAPACITY);
if (t > threshold) {
threshold = tableSizeFor(t);
}
} else if (s > threshold) {
resize();
}
for (Map.Entry<? extends K, ? extends V> e : m.entrySet()) {
K key = e.getKey();
V value = e.getValue();
putVal(hash(key), key, value, false, evict);
}
}
}
/**
* Returns the number of key-value mappings in this map.
*
* @return the number of key-value mappings in this map
*/
public int size() {
return size;
}
/**
* Returns {@code true} if this map contains no key-value mappings.
*
* @return {@code true} if this map contains no key-value mappings
*/
public boolean isEmpty() {
return size == 0;
}
/**
* Returns the value to which the specified key is mapped, or {@code null} if this map contains
* no mapping for the key.
*
* <p>More formally, if this map contains a mapping from a key {@code k} to a value {@code v}
* such that {@code (key==null ? k==null : key.equals(k))}, then this method returns {@code v};
* otherwise it returns {@code null}. (There can be at most one such mapping.)
*
* <p>A return value of {@code null} does not <i>necessarily</i> indicate that the map contains
* no mapping for the key; it's also possible that the map explicitly maps the key to {@code
* null}. The {@link #containsKey containsKey} operation may be used to distinguish these two
* cases.
*
* @see #put(Object, Object)
*/
public V get(Object key) {
Node<K, V> e;
return (e = getNode(hash(key), key)) == null ? null : e.value;
}
/**
* Implements Map.get and related methods
*
* @param hash hash for key
* @param key the key
* @return the node, or null if none
*/
final Node<K, V> getNode(int hash, Object key) {
Node<K, V>[] tab;
Node<K, V> first, e;
int n;
K k;
if ((tab = table) != null
&& (n = tab.length) > 0
&& (first = tab[(n - 1) & hash]) != null) {
if (first.hash == hash
&& // always check first node
((k = first.key) == key || (key != null && keyEquals(key, k)))) {
return first;
}
if ((e = first.next) != null) {
if (first instanceof TreeNode) {
return ((TreeNode<K, V>) first).getTreeNode(hash, key);
}
do {
if (e.hash == hash
&& ((k = e.key) == key || (key != null && keyEquals(key, k)))) {
return e;
}
} while ((e = e.next) != null);
}
}
return null;
}
/**
* Returns {@code true} if this map contains a mapping for the specified key.
*
* @param key The key whose presence in this map is to be tested
* @return {@code true} if this map contains a mapping for the specified key.
*/
public boolean containsKey(Object key) {
return getNode(hash(key), key) != null;
}
/**
* Associates the specified value with the specified key in this map. If the map previously
* contained a mapping for the key, the old value is replaced.
*
* @param key key with which the specified value is to be associated
* @param value value to be associated with the specified key
* @return the previous value associated with {@code key}, or {@code null} if there was no
* mapping for {@code key}. (A {@code null} return can also indicate that the map previously
* associated {@code null} with {@code key}.)
*/
public V put(K key, V value) {
return putVal(hash(key), key, value, false, true);
}
/**
* Implements Map.put and related methods
*
* @param hash hash for key
* @param key the key
* @param value the value to put
* @param onlyIfAbsent if true, don't change existing value
* @param evict if false, the table is in creation mode.
* @return previous value, or null if none
*/
final V putVal(int hash, K key, V value, boolean onlyIfAbsent, boolean evict) {
Node<K, V>[] tab;
Node<K, V> p;
int n, i;
if ((tab = table) == null || (n = tab.length) == 0) {
n = (tab = resize()).length;
}
if ((p = tab[i = (n - 1) & hash]) == null) {
tab[i] = newNode(hash, key, value, null);
} else {
Node<K, V> e;
K k;
if (p.hash == hash && ((k = p.key) == key || (key != null && keyEquals(key, k)))) {
e = p;
} else if (p instanceof TreeNode) {
e = ((TreeNode<K, V>) p).putTreeVal(this, tab, hash, key, value);
} else {
for (int binCount = 0; ; ++binCount) {
if ((e = p.next) == null) {
p.next = newNode(hash, key, value, null);
if (binCount >= TREEIFY_THRESHOLD - 1) // -1 for 1st
{
treeifyBin(tab, hash);
}
break;
}
if (e.hash == hash
&& ((k = e.key) == key || (key != null && keyEquals(key, k)))) {
break;
}
p = e;
}
}
if (e != null) { // existing mapping for key
V oldValue = e.value;
if (!onlyIfAbsent || oldValue == null) {
e.value = value;
}
afterNodeAccess(e);
return oldValue;
}
}
++modCount;
if (++size > threshold) {
resize();
}
afterNodeInsertion(evict);
return null;
}
/**
* Initializes or doubles table size. If null, allocates in accord with initial capacity target
* held in field threshold. Otherwise, because we are using power-of-two expansion, the elements
* from each bin must either stay at same index, or move with a power of two offset in the new
* table.
*
* @return the table
*/
final Node<K, V>[] resize() {
Node<K, V>[] oldTab = table;
int oldCap = (oldTab == null) ? 0 : oldTab.length;
int oldThr = threshold;
int newCap, newThr = 0;
if (oldCap > 0) {
if (oldCap >= MAXIMUM_CAPACITY) {
threshold = Integer.MAX_VALUE;
return oldTab;
} else if ((newCap = oldCap << 1) < MAXIMUM_CAPACITY
&& oldCap >= DEFAULT_INITIAL_CAPACITY) {
newThr = oldThr << 1; // double threshold
}
} else if (oldThr > 0) // initial capacity was placed in threshold
{
newCap = oldThr;
} else { // zero initial threshold signifies using defaults
newCap = DEFAULT_INITIAL_CAPACITY;
newThr = (int) (DEFAULT_LOAD_FACTOR * DEFAULT_INITIAL_CAPACITY);
}
if (newThr == 0) {
float ft = (float) newCap * loadFactor;
newThr =
(newCap < MAXIMUM_CAPACITY && ft < (float) MAXIMUM_CAPACITY
? (int) ft
: Integer.MAX_VALUE);
}
threshold = newThr;
@SuppressWarnings({"unchecked"})
Node<K, V>[] newTab = (Node<K, V>[]) new Node[newCap];
table = newTab;
if (oldTab != null) {
for (int j = 0; j < oldCap; ++j) {
Node<K, V> e;
if ((e = oldTab[j]) != null) {
oldTab[j] = null;
if (e.next == null) {
newTab[e.hash & (newCap - 1)] = e;
} else if (e instanceof TreeNode) {
((TreeNode<K, V>) e).split(this, newTab, j, oldCap);
} else { // preserve order
Node<K, V> loHead = null, loTail = null;
Node<K, V> hiHead = null, hiTail = null;
Node<K, V> next;
do {
next = e.next;
if ((e.hash & oldCap) == 0) {
if (loTail == null) {
loHead = e;
} else {
loTail.next = e;
}
loTail = e;
} else {
if (hiTail == null) {
hiHead = e;
} else {
hiTail.next = e;
}
hiTail = e;
}
} while ((e = next) != null);
if (loTail != null) {
loTail.next = null;
newTab[j] = loHead;
}
if (hiTail != null) {
hiTail.next = null;
newTab[j + oldCap] = hiHead;
}
}
}
}
}
return newTab;
}
/**
* Replaces all linked nodes in bin at index for given hash unless table is too small, in which
* case resizes instead.
*/
final void treeifyBin(Node<K, V>[] tab, int hash) {
int n, index;
Node<K, V> e;
if (tab == null || (n = tab.length) < MIN_TREEIFY_CAPACITY) {
resize();
} else if ((e = tab[index = (n - 1) & hash]) != null) {
TreeNode<K, V> hd = null, tl = null;
do {
TreeNode<K, V> p = replacementTreeNode(e, null);
if (tl == null) {
hd = p;
} else {
p.prev = tl;
tl.next = p;
}
tl = p;
} while ((e = e.next) != null);
if ((tab[index] = hd) != null) {
hd.treeify(tab);
}
}
}
/**
* Copies all of the mappings from the specified map to this map. These mappings will replace
* any mappings that this map had for any of the keys currently in the specified map.
*
* @param m mappings to be stored in this map
* @throws NullPointerException if the specified map is null
*/
public void putAll(Map<? extends K, ? extends V> m) {
putMapEntries(m, true);
}
/**
* Removes the mapping for the specified key from this map if present.
*
* @param key key whose mapping is to be removed from the map
* @return the previous value associated with {@code key}, or {@code null} if there was no
* mapping for {@code key}. (A {@code null} return can also indicate that the map previously
* associated {@code null} with {@code key}.)
*/
public V remove(Object key) {
Node<K, V> e;
return (e = removeNode(hash(key), key, null, false, true)) == null ? null : e.value;
}
/**
* Implements Map.remove and related methods
*
* @param hash hash for key
* @param key the key
* @param value the value to match if matchValue, else ignored
* @param matchValue if true only remove if value is equal
* @param movable if false do not move other nodes while removing
* @return the node, or null if none
*/
final Node<K, V> removeNode(
int hash, Object key, Object value, boolean matchValue, boolean movable) {
Node<K, V>[] tab;
Node<K, V> p;
int n, index;
if ((tab = table) != null
&& (n = tab.length) > 0
&& (p = tab[index = (n - 1) & hash]) != null) {
Node<K, V> node = null, e;
K k;
V v;
if (p.hash == hash && ((k = p.key) == key || (key != null && keyEquals(key, k)))) {
node = p;
} else if ((e = p.next) != null) {
if (p instanceof TreeNode) {
node = ((TreeNode<K, V>) p).getTreeNode(hash, key);
} else {
do {
if (e.hash == hash
&& ((k = e.key) == key || (key != null && keyEquals(key, k)))) {
node = e;
break;
}
p = e;
} while ((e = e.next) != null);
}
}
if (node != null
&& (!matchValue
|| (v = node.value) == value
|| (value != null && valEquals(value, v)))) {
if (node instanceof TreeNode) {
((TreeNode<K, V>) node).removeTreeNode(this, tab, movable);
} else if (node == p) {
tab[index] = node.next;
} else {
p.next = node.next;
}
++modCount;
--size;
afterNodeRemoval(node);
return node;
}
}
return null;
}
/** Removes all of the mappings from this map. The map will be empty after this call returns. */
public void clear() {
Node<K, V>[] tab;
modCount++;
if ((tab = table) != null && size > 0) {
size = 0;
for (int i = 0; i < tab.length; ++i) {
tab[i] = null;
}
}
}
/**
* Returns {@code true} if this map maps one or more keys to the specified value.
*
* @param value value whose presence in this map is to be tested
* @return {@code true} if this map maps one or more keys to the specified value
*/
public boolean containsValue(Object value) {
Node<K, V>[] tab;
V v;
if ((tab = table) != null && size > 0) {
for (Node<K, V> e : tab) {
for (; e != null; e = e.next) {
if ((v = e.value) == value || (value != null && valEquals(value, v))) {
return true;
}
}
}
}
return false;
}
/**
* Returns a {@link Set} view of the keys contained in this map. The set is backed by the map,
* so changes to the map are reflected in the set, and vice-versa. If the map is modified while
* an iteration over the set is in progress (except through the iterator's own {@code remove}
* operation), the results of the iteration are undefined. The set supports element removal,
* which removes the corresponding mapping from the map, via the {@code Iterator.remove}, {@code
* Set.remove}, {@code removeAll}, {@code retainAll}, and {@code clear} operations. It does not
* support the {@code add} or {@code addAll} operations.
*
* @return a set view of the keys contained in this map
*/
public Set<K> keySet() {
Set<K> ks = keySet;
if (ks == null) {
ks = new KeySet();
keySet = ks;
}
return ks;
}
final class KeySet extends AbstractSet<K> {
public final int size() {
return size;
}
public final void clear() {
HashMap.this.clear();
}
public final Iterator<K> iterator() {
return new KeyIterator();
}
public final boolean contains(Object o) {
return containsKey(o);
}
public final boolean remove(Object key) {
return removeNode(hash(key), key, null, false, true) != null;
}
public final Spliterator<K> spliterator() {
return new KeySpliterator<>(HashMap.this, 0, -1, 0, 0);
}
public final void forEach(Consumer<? super K> action) {
Node<K, V>[] tab;
if (action == null) {
throw new NullPointerException();
}
if (size > 0 && (tab = table) != null) {
int mc = modCount;
for (Node<K, V> e : tab) {
for (; e != null; e = e.next) {
action.accept(e.key);
}
}
if (modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
}
/**
* Returns a {@link Collection} view of the values contained in this map. The collection is
* backed by the map, so changes to the map are reflected in the collection, and vice-versa. If
* the map is modified while an iteration over the collection is in progress (except through the
* iterator's own {@code remove} operation), the results of the iteration are undefined. The
* collection supports element removal, which removes the corresponding mapping from the map,
* via the {@code Iterator.remove}, {@code Collection.remove}, {@code removeAll}, {@code
* retainAll} and {@code clear} operations. It does not support the {@code add} or {@code
* addAll} operations.
*
* @return a view of the values contained in this map
*/
public Collection<V> values() {
Collection<V> vs = values;
if (vs == null) {
vs = new Values();
values = vs;
}
return vs;
}
final class Values extends AbstractCollection<V> {
public final int size() {
return size;
}
public final void clear() {
HashMap.this.clear();
}
public final Iterator<V> iterator() {
return new ValueIterator();
}
public final boolean contains(Object o) {
return containsValue(o);
}
public final Spliterator<V> spliterator() {
return new ValueSpliterator<>(HashMap.this, 0, -1, 0, 0);
}
public final void forEach(Consumer<? super V> action) {
Node<K, V>[] tab;
if (action == null) {
throw new NullPointerException();
}
if (size > 0 && (tab = table) != null) {
int mc = modCount;
for (Node<K, V> e : tab) {
for (; e != null; e = e.next) {
action.accept(e.value);
}
}
if (modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
}
/**
* Returns a {@link Set} view of the mappings contained in this map. The set is backed by the
* map, so changes to the map are reflected in the set, and vice-versa. If the map is modified
* while an iteration over the set is in progress (except through the iterator's own {@code
* remove} operation, or through the {@code setValue} operation on a map entry returned by the
* iterator) the results of the iteration are undefined. The set supports element removal, which
* removes the corresponding mapping from the map, via the {@code Iterator.remove}, {@code
* Set.remove}, {@code removeAll}, {@code retainAll} and {@code clear} operations. It does not
* support the {@code add} or {@code addAll} operations.
*
* @return a set view of the mappings contained in this map
*/
public Set<Map.Entry<K, V>> entrySet() {
Set<Map.Entry<K, V>> es;
return (es = entrySet) == null ? (entrySet = new EntrySet()) : es;
}
final class EntrySet extends AbstractSet<Map.Entry<K, V>> {
public final int size() {
return size;
}
public final void clear() {
HashMap.this.clear();
}
public final Iterator<Map.Entry<K, V>> iterator() {
return new EntryIterator();
}
public final boolean contains(Object o) {
if (!(o instanceof Map.Entry)) {
return false;
}
Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
Object key = e.getKey();
Node<K, V> candidate = getNode(hash(key), key);
return candidate != null && candidate.equals(e);
}
public final boolean remove(Object o) {
if (o instanceof Map.Entry) {
Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
Object key = e.getKey();
Object value = e.getValue();
return removeNode(hash(key), key, value, true, true) != null;
}
return false;
}
public final Spliterator<Map.Entry<K, V>> spliterator() {
return new EntrySpliterator<>(HashMap.this, 0, -1, 0, 0);
}
public final void forEach(Consumer<? super Map.Entry<K, V>> action) {
Node<K, V>[] tab;
if (action == null) {
throw new NullPointerException();
}
if (size > 0 && (tab = table) != null) {
int mc = modCount;
for (Node<K, V> e : tab) {
for (; e != null; e = e.next) {
action.accept(e);
}
}
if (modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
}
// Overrides of JDK8 Map extension methods
@Override
public V getOrDefault(Object key, V defaultValue) {
Node<K, V> e;
return (e = getNode(hash(key), key)) == null ? defaultValue : e.value;
}
@Override
public V putIfAbsent(K key, V value) {
return putVal(hash(key), key, value, true, true);
}
@Override
public boolean remove(Object key, Object value) {
return removeNode(hash(key), key, value, true, true) != null;
}
@Override
public boolean replace(K key, V oldValue, V newValue) {
Node<K, V> e;
V v;
if ((e = getNode(hash(key), key)) != null
&& ((v = e.value) == oldValue || (v != null && valEquals(oldValue, v)))) {
e.value = newValue;
afterNodeAccess(e);
return true;
}
return false;
}
@Override
public V replace(K key, V value) {
Node<K, V> e;
if ((e = getNode(hash(key), key)) != null) {
V oldValue = e.value;
e.value = value;
afterNodeAccess(e);
return oldValue;
}
return null;
}
/**
* {@inheritDoc}
*
* <p>This method will, on a best-effort basis, throw a {@link ConcurrentModificationException}
* if it is detected that the mapping function modifies this map during computation.
*
* @throws ConcurrentModificationException if it is detected that the mapping function modified
* this map
*/
@Override
public V computeIfAbsent(K key, Function<? super K, ? extends V> mappingFunction) {
if (mappingFunction == null) {
throw new NullPointerException();
}
int hash = hash(key);
Node<K, V>[] tab;
Node<K, V> first;
int n, i;
int binCount = 0;
TreeNode<K, V> t = null;
Node<K, V> old = null;
if (size > threshold || (tab = table) == null || (n = tab.length) == 0) {
n = (tab = resize()).length;
}
if ((first = tab[i = (n - 1) & hash]) != null) {
if (first instanceof TreeNode) {
old = (t = (TreeNode<K, V>) first).getTreeNode(hash, key);
} else {
Node<K, V> e = first;
K k;
do {
if (e.hash == hash
&& ((k = e.key) == key || (key != null && keyEquals(key, k)))) {
old = e;
break;
}
++binCount;
} while ((e = e.next) != null);
}
V oldValue;
if (old != null && (oldValue = old.value) != null) {
afterNodeAccess(old);
return oldValue;
}
}
int mc = modCount;
V v = mappingFunction.apply(key);
if (mc != modCount) {
throw new ConcurrentModificationException();
}
if (v == null) {
return null;
} else if (old != null) {
old.value = v;
afterNodeAccess(old);
return v;
} else if (t != null) {
t.putTreeVal(this, tab, hash, key, v);
} else {
tab[i] = newNode(hash, key, v, first);
if (binCount >= TREEIFY_THRESHOLD - 1) {
treeifyBin(tab, hash);
}
}
modCount = mc + 1;
++size;
afterNodeInsertion(true);
return v;
}
/**
* {@inheritDoc}
*
* <p>This method will, on a best-effort basis, throw a {@link ConcurrentModificationException}
* if it is detected that the remapping function modifies this map during computation.
*
* @throws ConcurrentModificationException if it is detected that the remapping function
* modified this map
*/
@Override
public V computeIfPresent(
K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
if (remappingFunction == null) {
throw new NullPointerException();
}
Node<K, V> e;
V oldValue;
int hash = hash(key);
if ((e = getNode(hash, key)) != null && (oldValue = e.value) != null) {
int mc = modCount;
V v = remappingFunction.apply(key, oldValue);
if (mc != modCount) {
throw new ConcurrentModificationException();
}
if (v != null) {
e.value = v;
afterNodeAccess(e);
return v;
} else {
removeNode(hash, key, null, false, true);
}
}
return null;
}
/**
* {@inheritDoc}
*
* <p>This method will, on a best-effort basis, throw a {@link ConcurrentModificationException}
* if it is detected that the remapping function modifies this map during computation.
*
* @throws ConcurrentModificationException if it is detected that the remapping function
* modified this map
*/
@Override
public V compute(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
if (remappingFunction == null) {
throw new NullPointerException();
}
int hash = hash(key);
Node<K, V>[] tab;
Node<K, V> first;
int n, i;
int binCount = 0;
TreeNode<K, V> t = null;
Node<K, V> old = null;
if (size > threshold || (tab = table) == null || (n = tab.length) == 0) {
n = (tab = resize()).length;
}
if ((first = tab[i = (n - 1) & hash]) != null) {
if (first instanceof TreeNode) {
old = (t = (TreeNode<K, V>) first).getTreeNode(hash, key);
} else {
Node<K, V> e = first;
K k;
do {
if (e.hash == hash
&& ((k = e.key) == key || (key != null && keyEquals(key, k)))) {
old = e;
break;
}
++binCount;
} while ((e = e.next) != null);
}
}
V oldValue = (old == null) ? null : old.value;
int mc = modCount;
V v = remappingFunction.apply(key, oldValue);
if (mc != modCount) {
throw new ConcurrentModificationException();
}
if (old != null) {
if (v != null) {
old.value = v;
afterNodeAccess(old);
} else {
removeNode(hash, key, null, false, true);
}
} else if (v != null) {
if (t != null) {
t.putTreeVal(this, tab, hash, key, v);
} else {
tab[i] = newNode(hash, key, v, first);
if (binCount >= TREEIFY_THRESHOLD - 1) {
treeifyBin(tab, hash);
}
}
modCount = mc + 1;
++size;
afterNodeInsertion(true);
}
return v;
}
/**
* {@inheritDoc}
*
* <p>This method will, on a best-effort basis, throw a {@link ConcurrentModificationException}
* if it is detected that the remapping function modifies this map during computation.
*
* @throws ConcurrentModificationException if it is detected that the remapping function
* modified this map
*/
@Override
public V merge(
K key, V value, BiFunction<? super V, ? super V, ? extends V> remappingFunction) {
if (value == null) {
throw new NullPointerException();
}
if (remappingFunction == null) {
throw new NullPointerException();
}
int hash = hash(key);
Node<K, V>[] tab;
Node<K, V> first;
int n, i;
int binCount = 0;
TreeNode<K, V> t = null;
Node<K, V> old = null;
if (size > threshold || (tab = table) == null || (n = tab.length) == 0) {
n = (tab = resize()).length;
}
if ((first = tab[i = (n - 1) & hash]) != null) {
if (first instanceof TreeNode) {
old = (t = (TreeNode<K, V>) first).getTreeNode(hash, key);
} else {
Node<K, V> e = first;
K k;
do {
if (e.hash == hash
&& ((k = e.key) == key || (key != null && keyEquals(key, k)))) {
old = e;
break;
}
++binCount;
} while ((e = e.next) != null);
}
}
if (old != null) {
V v;
if (old.value != null) {
int mc = modCount;
v = remappingFunction.apply(old.value, value);
if (mc != modCount) {
throw new ConcurrentModificationException();
}
} else {
v = value;
}
if (v != null) {
old.value = v;
afterNodeAccess(old);
} else {
removeNode(hash, key, null, false, true);
}
return v;
}
if (value != null) {
if (t != null) {
t.putTreeVal(this, tab, hash, key, value);
} else {
tab[i] = newNode(hash, key, value, first);
if (binCount >= TREEIFY_THRESHOLD - 1) {
treeifyBin(tab, hash);
}
}
++modCount;
++size;
afterNodeInsertion(true);
}
return value;
}
@Override
public void forEach(BiConsumer<? super K, ? super V> action) {
Node<K, V>[] tab;
if (action == null) {
throw new NullPointerException();
}
if (size > 0 && (tab = table) != null) {
int mc = modCount;
for (Node<K, V> e : tab) {
for (; e != null; e = e.next) {
action.accept(e.key, e.value);
}
}
if (modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
@Override
public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function) {
Node<K, V>[] tab;
if (function == null) {
throw new NullPointerException();
}
if (size > 0 && (tab = table) != null) {
int mc = modCount;
for (Node<K, V> e : tab) {
for (; e != null; e = e.next) {
e.value = function.apply(e.key, e.value);
}
}
if (modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
/* ------------------------------------------------------------ */
// Cloning and serialization
/**
* Returns a shallow copy of this {@code HashMap} instance: the keys and values themselves are
* not cloned.
*
* @return a shallow copy of this map
*/
@SuppressWarnings("unchecked")
@Override
public Object clone() {
HashMap<K, V> result;
try {
result = (HashMap<K, V>) super.clone();
} catch (CloneNotSupportedException e) {
// this shouldn't happen, since we are Cloneable
throw new InternalError(e);
}
result.reinitialize();
result.putMapEntries(this, false);
return result;
}
// These methods are also used when serializing HashSets
final float loadFactor() {
return loadFactor;
}
final int capacity() {
return (table != null)
? table.length
: (threshold > 0) ? threshold : DEFAULT_INITIAL_CAPACITY;
}
/**
* Save the state of the {@code HashMap} instance to a stream (i.e., serialize it).
*
* @serialData The <i>capacity</i> of the HashMap (the length of the bucket array) is emitted
* (int), followed by the <i>size</i> (an int, the number of key-value mappings), followed
* by the key (Object) and value (Object) for each key-value mapping. The key-value mappings
* are emitted in no particular order.
*/
private void writeObject(java.io.ObjectOutputStream s) throws IOException {
int buckets = capacity();
// Write out the threshold, loadfactor, and any hidden stuff
s.defaultWriteObject();
s.writeInt(buckets);
s.writeInt(size);
internalWriteEntries(s);
}
/** Reconstitute the {@code HashMap} instance from a stream (i.e., deserialize it). */
private void readObject(java.io.ObjectInputStream s)
throws IOException, ClassNotFoundException {
// Read in the threshold (ignored), loadfactor, and any hidden stuff
s.defaultReadObject();
reinitialize();
if (loadFactor <= 0 || Float.isNaN(loadFactor)) {
throw new InvalidObjectException("Illegal load factor: " + loadFactor);
}
s.readInt(); // Read and ignore number of buckets
int mappings = s.readInt(); // Read number of mappings (size)
if (mappings < 0) {
throw new InvalidObjectException("Illegal mappings count: " + mappings);
} else if (mappings > 0) { // (if zero, use defaults)
// Size the table using given load factor only if within
// range of 0.25...4.0
float lf = Math.min(Math.max(0.25f, loadFactor), 4.0f);
float fc = (float) mappings / lf + 1.0f;
int cap =
((fc < DEFAULT_INITIAL_CAPACITY)
? DEFAULT_INITIAL_CAPACITY
: (fc >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : tableSizeFor((int) fc));
float ft = (float) cap * lf;
threshold =
((cap < MAXIMUM_CAPACITY && ft < MAXIMUM_CAPACITY)
? (int) ft
: Integer.MAX_VALUE);
@SuppressWarnings({"unchecked"})
Node<K, V>[] tab = (Node<K, V>[]) new Node[cap];
table = tab;
// Read the keys and values, and put the mappings in the HashMap
for (int i = 0; i < mappings; i++) {
@SuppressWarnings("unchecked")
K key = (K) s.readObject();
@SuppressWarnings("unchecked")
V value = (V) s.readObject();
putVal(hash(key), key, value, false, false);
}
}
}
/* ------------------------------------------------------------ */
// iterators
abstract class HashIterator {
Node<K, V> next; // next entry to return
Node<K, V> current; // current entry
int expectedModCount; // for fast-fail
int index; // current slot
HashIterator() {
expectedModCount = modCount;
Node<K, V>[] t = table;
current = next = null;
index = 0;
if (t != null && size > 0) { // advance to first entry
do {} while (index < t.length && (next = t[index++]) == null);
}
}
public final boolean hasNext() {
return next != null;
}
final Node<K, V> nextNode() {
Node<K, V>[] t;
Node<K, V> e = next;
if (modCount != expectedModCount) {
throw new ConcurrentModificationException();
}
if (e == null) {
throw new NoSuchElementException();
}
if ((next = (current = e).next) == null && (t = table) != null) {
do {} while (index < t.length && (next = t[index++]) == null);
}
return e;
}
public final void remove() {
Node<K, V> p = current;
if (p == null) {
throw new IllegalStateException();
}
if (modCount != expectedModCount) {
throw new ConcurrentModificationException();
}
current = null;
K key = p.key;
removeNode(hash(key), key, null, false, false);
expectedModCount = modCount;
}
}
final class KeyIterator extends HashIterator implements Iterator<K> {
public final K next() {
return nextNode().key;
}
}
final class ValueIterator extends HashIterator implements Iterator<V> {
public final V next() {
return nextNode().value;
}
}
final class EntryIterator extends HashIterator implements Iterator<Map.Entry<K, V>> {
public final Map.Entry<K, V> next() {
return nextNode();
}
}
/* ------------------------------------------------------------ */
// spliterators
static class HashMapSpliterator<K, V> {
final HashMap<K, V> map;
Node<K, V> current; // current node
int index; // current index, modified on advance/split
int fence; // one past last index
int est; // size estimate
int expectedModCount; // for comodification checks
HashMapSpliterator(HashMap<K, V> m, int origin, int fence, int est, int expectedModCount) {
this.map = m;
this.index = origin;
this.fence = fence;
this.est = est;
this.expectedModCount = expectedModCount;
}
final int getFence() { // initialize fence and size on first use
int hi;
if ((hi = fence) < 0) {
HashMap<K, V> m = map;
est = m.size;
expectedModCount = m.modCount;
Node<K, V>[] tab = m.table;
hi = fence = (tab == null) ? 0 : tab.length;
}
return hi;
}
public final long estimateSize() {
getFence(); // force init
return (long) est;
}
}
static final class KeySpliterator<K, V> extends HashMapSpliterator<K, V>
implements Spliterator<K> {
KeySpliterator(HashMap<K, V> m, int origin, int fence, int est, int expectedModCount) {
super(m, origin, fence, est, expectedModCount);
}
public KeySpliterator<K, V> trySplit() {
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
return (lo >= mid || current != null)
? null
: new KeySpliterator<>(map, lo, index = mid, est >>>= 1, expectedModCount);
}
public void forEachRemaining(Consumer<? super K> action) {
int i, hi, mc;
if (action == null) {
throw new NullPointerException();
}
HashMap<K, V> m = map;
Node<K, V>[] tab = m.table;
if ((hi = fence) < 0) {
mc = expectedModCount = m.modCount;
hi = fence = (tab == null) ? 0 : tab.length;
} else {
mc = expectedModCount;
}
if (tab != null
&& tab.length >= hi
&& (i = index) >= 0
&& (i < (index = hi) || current != null)) {
Node<K, V> p = current;
current = null;
do {
if (p == null) {
p = tab[i++];
} else {
action.accept(p.key);
p = p.next;
}
} while (p != null || i < hi);
if (m.modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
public boolean tryAdvance(Consumer<? super K> action) {
int hi;
if (action == null) {
throw new NullPointerException();
}
Node<K, V>[] tab = map.table;
if (tab != null && tab.length >= (hi = getFence()) && index >= 0) {
while (current != null || index < hi) {
if (current == null) {
current = tab[index++];
} else {
K k = current.key;
current = current.next;
action.accept(k);
if (map.modCount != expectedModCount) {
throw new ConcurrentModificationException();
}
return true;
}
}
}
return false;
}
public int characteristics() {
return (fence < 0 || est == map.size ? Spliterator.SIZED : 0) | Spliterator.DISTINCT;
}
}
static final class ValueSpliterator<K, V> extends HashMapSpliterator<K, V>
implements Spliterator<V> {
ValueSpliterator(HashMap<K, V> m, int origin, int fence, int est, int expectedModCount) {
super(m, origin, fence, est, expectedModCount);
}
public ValueSpliterator<K, V> trySplit() {
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
return (lo >= mid || current != null)
? null
: new ValueSpliterator<>(map, lo, index = mid, est >>>= 1, expectedModCount);
}
public void forEachRemaining(Consumer<? super V> action) {
int i, hi, mc;
if (action == null) {
throw new NullPointerException();
}
HashMap<K, V> m = map;
Node<K, V>[] tab = m.table;
if ((hi = fence) < 0) {
mc = expectedModCount = m.modCount;
hi = fence = (tab == null) ? 0 : tab.length;
} else {
mc = expectedModCount;
}
if (tab != null
&& tab.length >= hi
&& (i = index) >= 0
&& (i < (index = hi) || current != null)) {
Node<K, V> p = current;
current = null;
do {
if (p == null) {
p = tab[i++];
} else {
action.accept(p.value);
p = p.next;
}
} while (p != null || i < hi);
if (m.modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
public boolean tryAdvance(Consumer<? super V> action) {
int hi;
if (action == null) {
throw new NullPointerException();
}
Node<K, V>[] tab = map.table;
if (tab != null && tab.length >= (hi = getFence()) && index >= 0) {
while (current != null || index < hi) {
if (current == null) {
current = tab[index++];
} else {
V v = current.value;
current = current.next;
action.accept(v);
if (map.modCount != expectedModCount) {
throw new ConcurrentModificationException();
}
return true;
}
}
}
return false;
}
public int characteristics() {
return (fence < 0 || est == map.size ? Spliterator.SIZED : 0);
}
}
static final class EntrySpliterator<K, V> extends HashMapSpliterator<K, V>
implements Spliterator<Map.Entry<K, V>> {
EntrySpliterator(HashMap<K, V> m, int origin, int fence, int est, int expectedModCount) {
super(m, origin, fence, est, expectedModCount);
}
public EntrySpliterator<K, V> trySplit() {
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
return (lo >= mid || current != null)
? null
: new EntrySpliterator<>(map, lo, index = mid, est >>>= 1, expectedModCount);
}
public void forEachRemaining(Consumer<? super Map.Entry<K, V>> action) {
int i, hi, mc;
if (action == null) {
throw new NullPointerException();
}
HashMap<K, V> m = map;
Node<K, V>[] tab = m.table;
if ((hi = fence) < 0) {
mc = expectedModCount = m.modCount;
hi = fence = (tab == null) ? 0 : tab.length;
} else {
mc = expectedModCount;
}
if (tab != null
&& tab.length >= hi
&& (i = index) >= 0
&& (i < (index = hi) || current != null)) {
Node<K, V> p = current;
current = null;
do {
if (p == null) {
p = tab[i++];
} else {
action.accept(p);
p = p.next;
}
} while (p != null || i < hi);
if (m.modCount != mc) {
throw new ConcurrentModificationException();
}
}
}
public boolean tryAdvance(Consumer<? super Map.Entry<K, V>> action) {
int hi;
if (action == null) {
throw new NullPointerException();
}
Node<K, V>[] tab = map.table;
if (tab != null && tab.length >= (hi = getFence()) && index >= 0) {
while (current != null || index < hi) {
if (current == null) {
current = tab[index++];
} else {
Node<K, V> e = current;
current = current.next;
action.accept(e);
if (map.modCount != expectedModCount) {
throw new ConcurrentModificationException();
}
return true;
}
}
}
return false;
}
public int characteristics() {
return (fence < 0 || est == map.size ? Spliterator.SIZED : 0) | Spliterator.DISTINCT;
}
}
/* ------------------------------------------------------------ */
// LinkedHashMap support
/*
* The following package-protected methods are designed to be
* overridden by LinkedHashMap, but not by any other subclass.
* Nearly all other internal methods are also package-protected
* but are declared final, so can be used by LinkedHashMap, view
* classes, and HashSet.
*/
protected abstract Node<K, V> newNode(int hash, K key, V value, Node<K, V> next);
// For conversion from TreeNodes to plain nodes
protected abstract Node<K, V> replacementNode(Node<K, V> p, Node<K, V> next);
// Create a tree bin node
protected abstract TreeNode<K, V> newTreeNode(int hash, K key, V value, Node<K, V> next);
// {
// return new TreeNode<>(hash, key, value, next);
// }
// For treeifyBin
protected abstract TreeNode<K, V> replacementTreeNode(Node<K, V> p, Node<K, V> next);
// {
// return new TreeNode<>(p.hash, p.key, p.value, next);
// }
/** Reset to initial default state. Called by clone and readObject. */
void reinitialize() {
table = null;
entrySet = null;
keySet = null;
values = null;
modCount = 0;
threshold = 0;
size = 0;
}
// Callbacks to allow LinkedHashMap post-actions
void afterNodeAccess(Node<K, V> p) {}
void afterNodeInsertion(boolean evict) {}
void afterNodeRemoval(Node<K, V> p) {}
// Called only from writeObject, to ensure compatible ordering.
void internalWriteEntries(java.io.ObjectOutputStream s) throws IOException {
Node<K, V>[] tab;
if (size > 0 && (tab = table) != null) {
for (Node<K, V> e : tab) {
for (; e != null; e = e.next) {
s.writeObject(e.key);
s.writeObject(e.value);
}
}
}
}
/* ------------------------------------------------------------ */
// Tree bins
/**
* Entry for Tree bins. Extends Entry (which in turn extends Node) so can be used as extension
* of either regular or linked node.
*/
abstract static class TreeNode<K, V> extends Entry<K, V> {
protected abstract boolean keyEquals(Object key, K k);
protected abstract boolean valEquals(Object value, V v);
TreeNode<K, V> parent; // red-black tree links
TreeNode<K, V> left;
TreeNode<K, V> right;
TreeNode<K, V> prev; // needed to unlink next upon deletion
boolean red;
TreeNode(int hash, K key, V val, Node<K, V> next) {
super(hash, key, val, next);
}
/** Returns root of tree containing this node. */
final TreeNode<K, V> root() {
for (TreeNode<K, V> r = this, p; ; ) {
if ((p = r.parent) == null) {
return r;
}
r = p;
}
}
/** Ensures that the given root is the first node of its bin. */
static <K, V> void moveRootToFront(Node<K, V>[] tab, TreeNode<K, V> root) {
int n;
if (root != null && tab != null && (n = tab.length) > 0) {
int index = (n - 1) & root.hash;
TreeNode<K, V> first = (TreeNode<K, V>) tab[index];
if (root != first) {
Node<K, V> rn;
tab[index] = root;
TreeNode<K, V> rp = root.prev;
if ((rn = root.next) != null) {
((TreeNode<K, V>) rn).prev = rp;
}
if (rp != null) {
rp.next = rn;
}
if (first != null) {
first.prev = root;
}
root.next = first;
root.prev = null;
}
assert checkInvariants(root);
}
}
/**
* Finds the node starting at root p with the given hash and key. The kc argument caches
* comparableClassFor(key) upon first use comparing keys.
*/
final TreeNode<K, V> find(int h, Object k, Class<?> kc) {
TreeNode<K, V> p = this;
do {
int ph, dir;
K pk;
TreeNode<K, V> pl = p.left, pr = p.right, q;
if ((ph = p.hash) > h) {
p = pl;
} else if (ph < h) {
p = pr;
} else if ((pk = p.key) == k || (k != null && keyEquals(k, pk))) {
return p;
} else if (pl == null) {
p = pr;
} else if (pr == null) {
p = pl;
} else if ((kc != null || (kc = comparableClassFor(k)) != null)
&& (dir = compareComparables(kc, k, pk)) != 0) {
p = (dir < 0) ? pl : pr;
} else if ((q = pr.find(h, k, kc)) != null) {
return q;
} else {
p = pl;
}
} while (p != null);
return null;
}
/** Calls find for root node. */
final TreeNode<K, V> getTreeNode(int h, Object k) {
return ((parent != null) ? root() : this).find(h, k, null);
}
/**
* Tie-breaking utility for ordering insertions when equal hashCodes and non-comparable. We
* don't require a total order, just a consistent insertion rule to maintain equivalence
* across rebalancings. Tie-breaking further than necessary simplifies testing a bit.
*/
static int tieBreakOrder(Object a, Object b) {
int d;
if (a == null
|| b == null
|| (d = a.getClass().getName().compareTo(b.getClass().getName())) == 0) {
d = (System.identityHashCode(a) <= System.identityHashCode(b) ? -1 : 1);
}
return d;
}
/**
* Forms tree of the nodes linked from this node.
*
* @return root of tree
*/
final void treeify(Node<K, V>[] tab) {
TreeNode<K, V> root = null;
for (TreeNode<K, V> x = this, next; x != null; x = next) {
next = (TreeNode<K, V>) x.next;
x.left = x.right = null;
if (root == null) {
x.parent = null;
x.red = false;
root = x;
} else {
K k = x.key;
int h = x.hash;
Class<?> kc = null;
for (TreeNode<K, V> p = root; ; ) {
int dir, ph;
K pk = p.key;
if ((ph = p.hash) > h) {
dir = -1;
} else if (ph < h) {
dir = 1;
} else if ((kc == null && (kc = comparableClassFor(k)) == null)
|| (dir = compareComparables(kc, k, pk)) == 0) {
dir = tieBreakOrder(k, pk);
}
TreeNode<K, V> xp = p;
if ((p = (dir <= 0) ? p.left : p.right) == null) {
x.parent = xp;
if (dir <= 0) {
xp.left = x;
} else {
xp.right = x;
}
root = balanceInsertion(root, x);
break;
}
}
}
}
moveRootToFront(tab, root);
}
/** Returns a list of non-TreeNodes replacing those linked from this node. */
final Node<K, V> untreeify(HashMap<K, V> map) {
Node<K, V> hd = null, tl = null;
for (Node<K, V> q = this; q != null; q = q.next) {
Node<K, V> p = map.replacementNode(q, null);
if (tl == null) {
hd = p;
} else {
tl.next = p;
}
tl = p;
}
return hd;
}
/** Tree version of putVal. */
final TreeNode<K, V> putTreeVal(HashMap<K, V> map, Node<K, V>[] tab, int h, K k, V v) {
Class<?> kc = null;
boolean searched = false;
TreeNode<K, V> root = (parent != null) ? root() : this;
for (TreeNode<K, V> p = root; ; ) {
int dir, ph;
K pk;
if ((ph = p.hash) > h) {
dir = -1;
} else if (ph < h) {
dir = 1;
} else if ((pk = p.key) == k || (k != null && keyEquals(k, pk))) {
return p;
} else if ((kc == null && (kc = comparableClassFor(k)) == null)
|| (dir = compareComparables(kc, k, pk)) == 0) {
if (!searched) {
TreeNode<K, V> q, ch;
searched = true;
if (((ch = p.left) != null && (q = ch.find(h, k, kc)) != null)
|| ((ch = p.right) != null && (q = ch.find(h, k, kc)) != null)) {
return q;
}
}
dir = tieBreakOrder(k, pk);
}
TreeNode<K, V> xp = p;
if ((p = (dir <= 0) ? p.left : p.right) == null) {
Node<K, V> xpn = xp.next;
TreeNode<K, V> x = map.newTreeNode(h, k, v, xpn);
if (dir <= 0) {
xp.left = x;
} else {
xp.right = x;
}
xp.next = x;
x.parent = x.prev = xp;
if (xpn != null) {
((TreeNode<K, V>) xpn).prev = x;
}
moveRootToFront(tab, balanceInsertion(root, x));
return null;
}
}
}
/**
* Removes the given node, that must be present before this call. This is messier than
* typical red-black deletion code because we cannot swap the contents of an interior node
* with a leaf successor that is pinned by "next" pointers that are accessible independently
* during traversal. So instead we swap the tree linkages. If the current tree appears to
* have too few nodes, the bin is converted back to a plain bin. (The test triggers
* somewhere between 2 and 6 nodes, depending on tree structure).
*/
final void removeTreeNode(HashMap<K, V> map, Node<K, V>[] tab, boolean movable) {
int n;
if (tab == null || (n = tab.length) == 0) {
return;
}
int index = (n - 1) & hash;
TreeNode<K, V> first = (TreeNode<K, V>) tab[index], root = first, rl;
TreeNode<K, V> succ = (TreeNode<K, V>) next, pred = prev;
if (pred == null) {
tab[index] = first = succ;
} else {
pred.next = succ;
}
if (succ != null) {
succ.prev = pred;
}
if (first == null) {
return;
}
if (root.parent != null) {
root = root.root();
}
if (root == null || root.right == null || (rl = root.left) == null || rl.left == null) {
tab[index] = first.untreeify(map); // too small
return;
}
TreeNode<K, V> p = this, pl = left, pr = right, replacement;
if (pl != null && pr != null) {
TreeNode<K, V> s = pr, sl;
while ((sl = s.left) != null) // find successor
{
s = sl;
}
boolean c = s.red;
s.red = p.red;
p.red = c; // swap colors
TreeNode<K, V> sr = s.right;
TreeNode<K, V> pp = p.parent;
if (s == pr) { // p was s's direct parent
p.parent = s;
s.right = p;
} else {
TreeNode<K, V> sp = s.parent;
if ((p.parent = sp) != null) {
if (s == sp.left) {
sp.left = p;
} else {
sp.right = p;
}
}
if ((s.right = pr) != null) {
pr.parent = s;
}
}
p.left = null;
if ((p.right = sr) != null) {
sr.parent = p;
}
if ((s.left = pl) != null) {
pl.parent = s;
}
if ((s.parent = pp) == null) {
root = s;
} else if (p == pp.left) {
pp.left = s;
} else {
pp.right = s;
}
if (sr != null) {
replacement = sr;
} else {
replacement = p;
}
} else if (pl != null) {
replacement = pl;
} else if (pr != null) {
replacement = pr;
} else {
replacement = p;
}
if (replacement != p) {
TreeNode<K, V> pp = replacement.parent = p.parent;
if (pp == null) {
root = replacement;
} else if (p == pp.left) {
pp.left = replacement;
} else {
pp.right = replacement;
}
p.left = p.right = p.parent = null;
}
TreeNode<K, V> r = p.red ? root : balanceDeletion(root, replacement);
if (replacement == p) { // detach
TreeNode<K, V> pp = p.parent;
p.parent = null;
if (pp != null) {
if (p == pp.left) {
pp.left = null;
} else if (p == pp.right) {
pp.right = null;
}
}
}
if (movable) {
moveRootToFront(tab, r);
}
}
/**
* Splits nodes in a tree bin into lower and upper tree bins, or untreeifies if now too
* small. Called only from resize; see above discussion about split bits and indices.
*
* @param map the map
* @param tab the table for recording bin heads
* @param index the index of the table being split
* @param bit the bit of hash to split on
*/
final void split(HashMap<K, V> map, Node<K, V>[] tab, int index, int bit) {
TreeNode<K, V> b = this;
// Relink into lo and hi lists, preserving order
TreeNode<K, V> loHead = null, loTail = null;
TreeNode<K, V> hiHead = null, hiTail = null;
int lc = 0, hc = 0;
for (TreeNode<K, V> e = b, next; e != null; e = next) {
next = (TreeNode<K, V>) e.next;
e.next = null;
if ((e.hash & bit) == 0) {
if ((e.prev = loTail) == null) {
loHead = e;
} else {
loTail.next = e;
}
loTail = e;
++lc;
} else {
if ((e.prev = hiTail) == null) {
hiHead = e;
} else {
hiTail.next = e;
}
hiTail = e;
++hc;
}
}
if (loHead != null) {
if (lc <= UNTREEIFY_THRESHOLD) {
tab[index] = loHead.untreeify(map);
} else {
tab[index] = loHead;
if (hiHead != null) // (else is already treeified)
{
loHead.treeify(tab);
}
}
}
if (hiHead != null) {
if (hc <= UNTREEIFY_THRESHOLD) {
tab[index + bit] = hiHead.untreeify(map);
} else {
tab[index + bit] = hiHead;
if (loHead != null) {
hiHead.treeify(tab);
}
}
}
}
/* ------------------------------------------------------------ */
// Red-black tree methods, all adapted from CLR
static <K, V> TreeNode<K, V> rotateLeft(TreeNode<K, V> root, TreeNode<K, V> p) {
TreeNode<K, V> r, pp, rl;
if (p != null && (r = p.right) != null) {
if ((rl = p.right = r.left) != null) {
rl.parent = p;
}
if ((pp = r.parent = p.parent) == null) {
(root = r).red = false;
} else if (pp.left == p) {
pp.left = r;
} else {
pp.right = r;
}
r.left = p;
p.parent = r;
}
return root;
}
static <K, V> TreeNode<K, V> rotateRight(TreeNode<K, V> root, TreeNode<K, V> p) {
TreeNode<K, V> l, pp, lr;
if (p != null && (l = p.left) != null) {
if ((lr = p.left = l.right) != null) {
lr.parent = p;
}
if ((pp = l.parent = p.parent) == null) {
(root = l).red = false;
} else if (pp.right == p) {
pp.right = l;
} else {
pp.left = l;
}
l.right = p;
p.parent = l;
}
return root;
}
static <K, V> TreeNode<K, V> balanceInsertion(TreeNode<K, V> root, TreeNode<K, V> x) {
x.red = true;
for (TreeNode<K, V> xp, xpp, xppl, xppr; ; ) {
if ((xp = x.parent) == null) {
x.red = false;
return x;
} else if (!xp.red || (xpp = xp.parent) == null) {
return root;
}
if (xp == (xppl = xpp.left)) {
if ((xppr = xpp.right) != null && xppr.red) {
xppr.red = false;
xp.red = false;
xpp.red = true;
x = xpp;
} else {
if (x == xp.right) {
root = rotateLeft(root, x = xp);
xpp = (xp = x.parent) == null ? null : xp.parent;
}
if (xp != null) {
xp.red = false;
if (xpp != null) {
xpp.red = true;
root = rotateRight(root, xpp);
}
}
}
} else {
if (xppl != null && xppl.red) {
xppl.red = false;
xp.red = false;
xpp.red = true;
x = xpp;
} else {
if (x == xp.left) {
root = rotateRight(root, x = xp);
xpp = (xp = x.parent) == null ? null : xp.parent;
}
if (xp != null) {
xp.red = false;
if (xpp != null) {
xpp.red = true;
root = rotateLeft(root, xpp);
}
}
}
}
}
}
static <K, V> TreeNode<K, V> balanceDeletion(TreeNode<K, V> root, TreeNode<K, V> x) {
for (TreeNode<K, V> xp, xpl, xpr; ; ) {
if (x == null || x == root) {
return root;
} else if ((xp = x.parent) == null) {
x.red = false;
return x;
} else if (x.red) {
x.red = false;
return root;
} else if ((xpl = xp.left) == x) {
if ((xpr = xp.right) != null && xpr.red) {
xpr.red = false;
xp.red = true;
root = rotateLeft(root, xp);
xpr = (xp = x.parent) == null ? null : xp.right;
}
if (xpr == null) {
x = xp;
} else {
TreeNode<K, V> sl = xpr.left, sr = xpr.right;
if ((sr == null || !sr.red) && (sl == null || !sl.red)) {
xpr.red = true;
x = xp;
} else {
if (sr == null || !sr.red) {
if (sl != null) {
sl.red = false;
}
xpr.red = true;
root = rotateRight(root, xpr);
xpr = (xp = x.parent) == null ? null : xp.right;
}
if (xpr != null) {
xpr.red = (xp != null) && xp.red;
if ((sr = xpr.right) != null) {
sr.red = false;
}
}
if (xp != null) {
xp.red = false;
root = rotateLeft(root, xp);
}
x = root;
}
}
} else { // symmetric
if (xpl != null && xpl.red) {
xpl.red = false;
xp.red = true;
root = rotateRight(root, xp);
xpl = (xp = x.parent) == null ? null : xp.left;
}
if (xpl == null) {
x = xp;
} else {
TreeNode<K, V> sl = xpl.left, sr = xpl.right;
if ((sl == null || !sl.red) && (sr == null || !sr.red)) {
xpl.red = true;
x = xp;
} else {
if (sl == null || !sl.red) {
if (sr != null) {
sr.red = false;
}
xpl.red = true;
root = rotateLeft(root, xpl);
xpl = (xp = x.parent) == null ? null : xp.left;
}
if (xpl != null) {
xpl.red = (xp != null) && xp.red;
if ((sl = xpl.left) != null) {
sl.red = false;
}
}
if (xp != null) {
xp.red = false;
root = rotateRight(root, xp);
}
x = root;
}
}
}
}
}
/** Recursive invariant check */
static <K, V> boolean checkInvariants(TreeNode<K, V> t) {
TreeNode<K, V> tp = t.parent,
tl = t.left,
tr = t.right,
tb = t.prev,
tn = (TreeNode<K, V>) t.next;
if (tb != null && tb.next != t) {
return false;
}
if (tn != null && tn.prev != t) {
return false;
}
if (tp != null && t != tp.left && t != tp.right) {
return false;
}
if (tl != null && (tl.parent != t || tl.hash > t.hash)) {
return false;
}
if (tr != null && (tr.parent != t || tr.hash < t.hash)) {
return false;
}
if (t.red && tl != null && tl.red && tr != null && tr.red) {
return false;
}
if (tl != null && !checkInvariants(tl)) {
return false;
}
return tr == null || checkInvariants(tr);
}
}
static class Entry<K, V> extends Node<K, V> {
Entry<K, V> before, after;
Entry(int hash, K key, V value, Node<K, V> next) {
super(hash, key, value, next);
}
}
}
