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	/*
	* Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.util;

	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.function.BiConsumer;
	import java.util.function.BiFunction;
	import java.util.function.Consumer;
	import java.util.function.Function;
	import sun.misc.SharedSecrets;

	/**
	* Hash table based implementation of the <tt>Map</tt> interface. This
	* implementation provides all of the optional map operations, and permits
	* <tt>null</tt> values and the <tt>null</tt> key. (The <tt>HashMap</tt>
	* class is roughly equivalent to <tt>Hashtable</tt>, except that it is
	* unsynchronized and permits nulls.) This class makes no guarantees as to
	* the order of the map; in particular, it does not guarantee that the order
	* will remain constant over time.
	*
	* <p>This implementation provides constant-time performance for the basic
	* operations (<tt>get</tt> and <tt>put</tt>), assuming the hash function
	* disperses the elements properly among the buckets. Iteration over
	* collection views requires time proportional to the "capacity" of the
	* <tt>HashMap</tt> instance (the number of buckets) plus its size (the number
	* of key-value mappings). Thus, it's very important not to set the initial
	* capacity too high (or the load factor too low) if iteration performance is
	* important.
	*
	* <p>An instance of <tt>HashMap</tt> has two parameters that affect its
	* performance: <i>initial capacity</i> and <i>load factor</i>. The
	* <i>capacity</i> is the number of buckets in the hash table, and the initial
	* capacity is simply the capacity at the time the hash table is created. The
	* <i>load factor</i> is a measure of how full the hash table is allowed to
	* get before its capacity is automatically increased. When the number of
	* entries in the hash table exceeds the product of the load factor and the
	* current capacity, the hash table is <i>rehashed</i> (that is, internal data
	* structures are rebuilt) so that the hash table has approximately twice the
	* number of buckets.
	*
	* <p>As a general rule, the default load factor (.75) offers a good
	* tradeoff between time and space costs. Higher values decrease the
	* space overhead but increase the lookup cost (reflected in most of
	* the operations of the <tt>HashMap</tt> class, including
	* <tt>get</tt> and <tt>put</tt>). The expected number of entries in
	* the map and its load factor should be taken into account when
	* setting its initial capacity, so as to minimize the number of
	* rehash operations. If the initial capacity is greater than the
	* maximum number of entries divided by the load factor, no rehash
	* operations will ever occur.
	*
	* <p>If many mappings are to be stored in a <tt>HashMap</tt>
	* instance, creating it with a sufficiently large capacity will allow
	* the mappings to be stored more efficiently than letting it perform
	* automatic rehashing as needed to grow the table. Note that using
	* many keys with the same {@code hashCode()} is a sure way to slow
	* down performance of any hash table. To ameliorate impact, when keys
	* are {@link Comparable}, this class may use comparison order among
	* keys to help break ties.
	*
	* <p><strong>Note that this implementation is not synchronized.</strong>
	* If multiple threads access a hash map concurrently, and at least one of
	* the threads modifies the map structurally, it <i>must</i> be
	* synchronized externally. (A structural modification is any operation
	* that adds or deletes one or more mappings; merely changing the value
	* associated with a key that an instance already contains is not a
	* structural modification.) This is typically accomplished by
	* synchronizing on some object that naturally encapsulates the map.
	*
	* If no such object exists, the map should be "wrapped" using the
	* {@link Collections#synchronizedMap Collections.synchronizedMap}
	* method. This is best done at creation time, to prevent accidental
	* unsynchronized access to the map:<pre>
	* Map m = Collections.synchronizedMap(new HashMap(...));</pre>
	*
	* <p>The iterators returned by all of this class's "collection view methods"
	* are <i>fail-fast</i>: if the map is structurally modified at any time after
	* the iterator is created, in any way except through the iterator's own
	* <tt>remove</tt> method, the iterator will throw a
	* {@link ConcurrentModificationException}. Thus, in the face of concurrent
	* modification, the iterator fails quickly and cleanly, rather than risking
	* arbitrary, non-deterministic behavior at an undetermined time in the
	* future.
	*
	* <p>Note that the fail-fast behavior of an iterator cannot be guaranteed
	* as it is, generally speaking, impossible to make any hard guarantees in the
	* presence of unsynchronized concurrent modification. Fail-fast iterators
	* throw <tt>ConcurrentModificationException</tt> on a best-effort basis.
	* Therefore, it would be wrong to write a program that depended on this
	* exception for its correctness: <i>the fail-fast behavior of iterators
	* should be used only to detect bugs.</i>
	*
	* <p>This class is a member of the
	* <a href="{@docRoot}/../technotes/guides/collections/index.html">
	* Java Collections Framework</a>.
	*
	* @param <K> the type of keys maintained by this map
	* @param <V> the type of mapped values
	*
	* @author Doug Lea
	* @author Josh Bloch
	* @author Arthur van Hoff
	* @author Neal Gafter
	* @see Object#hashCode()
	* @see Collection
	* @see Map
	* @see TreeMap
	* @see Hashtable
	* @since 1.2
	*/
	public class HashMap<K,V> extends AbstractMap<K,V>
	implements Map<K,V>, Cloneable, Serializable {

	private static final long serialVersionUID = 362498820763181265L;

	/*
	* 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 types 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;
	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 final 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.
	*/
	static final int hash(Object key) {
	int h;
	return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);
	}

	/**
	* 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; Type t; ParameterizedType p;
	if ((c = x.getClass()) == String.class) // bypass checks
	return c;
	if ((ts = c.getGenericInterfaces()) != null) {
	for (int i = 0; i < ts.length; ++i) {
	if (((t = ts[i]) 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 <tt>HashMap</tt> 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 <tt>HashMap</tt> 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 <tt>HashMap</tt> 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 <tt>HashMap</tt> with the same mappings as the
	* specified <tt>Map</tt>. The <tt>HashMap</tt> is created with
	* default load factor (0.75) and an initial capacity sufficient to
	* hold the mappings in the specified <tt>Map</tt>.
	*
	* @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 <tt>true</tt> if this map contains no key-value mappings.
	*
	* @return <tt>true</tt> 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 && key.equals(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 && key.equals(k))))
	return e;
	} while ((e = e.next) != null);
	}
	}
	return null;
	}

	/**
	* Returns <tt>true</tt> if this map contains a mapping for the
	* specified key.
	*
	* @param key The key whose presence in this map is to be tested
	* @return <tt>true</tt> 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 <tt>key</tt>, or
	* <tt>null</tt> if there was no mapping for <tt>key</tt>.
	* (A <tt>null</tt> return can also indicate that the map
	* previously associated <tt>null</tt> with <tt>key</tt>.)
	*/
	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 && key.equals(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 && key.equals(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({"rawtypes","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 <tt>key</tt>, or
	* <tt>null</tt> if there was no mapping for <tt>key</tt>.
	* (A <tt>null</tt> return can also indicate that the map
	* previously associated <tt>null</tt> with <tt>key</tt>.)
	*/
	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 && key.equals(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 && key.equals(k)))) {
	node = e;
	break;
	}
	p = e;
	} while ((e = e.next) != null);
	}
	}
	if (node != null && (!matchValue \|\| (v = node.value) == value \|\|
	(value != null && value.equals(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 <tt>true</tt> 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 <tt>true</tt> 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 (int i = 0; i < tab.length; ++i) {
	for (Node<K,V> e = tab[i]; e != null; e = e.next) {
	if ((v = e.value) == value \|\|
	(value != null && value.equals(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 <tt>remove</tt> operation), the results of
	* the iteration are undefined. The set supports element removal,
	* which removes the corresponding mapping from the map, via the
	* <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
	* operations. It does not support the <tt>add</tt> or <tt>addAll</tt>
	* 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 (int i = 0; i < tab.length; ++i) {
	for (Node<K,V> e = tab[i]; 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 <tt>remove</tt> operation),
	* the results of the iteration are undefined. The collection
	* supports element removal, which removes the corresponding
	* mapping from the map, via the <tt>Iterator.remove</tt>,
	* <tt>Collection.remove</tt>, <tt>removeAll</tt>,
	* <tt>retainAll</tt> and <tt>clear</tt> operations. It does not
	* support the <tt>add</tt> or <tt>addAll</tt> 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 (int i = 0; i < tab.length; ++i) {
	for (Node<K,V> e = tab[i]; 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 <tt>remove</tt> operation, or through the
	* <tt>setValue</tt> 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 <tt>Iterator.remove</tt>,
	* <tt>Set.remove</tt>, <tt>removeAll</tt>, <tt>retainAll</tt> and
	* <tt>clear</tt> operations. It does not support the
	* <tt>add</tt> or <tt>addAll</tt> 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 (int i = 0; i < tab.length; ++i) {
	for (Node<K,V> e = tab[i]; 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 && v.equals(oldValue)))) {
	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;
	}

	@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 && key.equals(k)))) {
	old = e;
	break;
	}
	++binCount;
	} while ((e = e.next) != null);
	}
	V oldValue;
	if (old != null && (oldValue = old.value) != null) {
	afterNodeAccess(old);
	return oldValue;
	}
	}
	V v = mappingFunction.apply(key);
	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;
	++size;
	afterNodeInsertion(true);
	return v;
	}

	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) {
	V v = remappingFunction.apply(key, oldValue);
	if (v != null) {
	e.value = v;
	afterNodeAccess(e);
	return v;
	}
	else
	removeNode(hash, key, null, false, true);
	}
	return null;
	}

	@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 && key.equals(k)))) {
	old = e;
	break;
	}
	++binCount;
	} while ((e = e.next) != null);
	}
	}
	V oldValue = (old == null) ? null : old.value;
	V v = remappingFunction.apply(key, oldValue);
	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;
	++size;
	afterNodeInsertion(true);
	}
	return v;
	}

	@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 && key.equals(k)))) {
	old = e;
	break;
	}
	++binCount;
	} while ((e = e.next) != null);
	}
	}
	if (old != null) {
	V v;
	if (old.value != null)
	v = remappingFunction.apply(old.value, value);
	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 (int i = 0; i < tab.length; ++i) {
	for (Node<K,V> e = tab[i]; 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 (int i = 0; i < tab.length; ++i) {
	for (Node<K,V> e = tab[i]; 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 <tt>HashMap</tt> 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 <tt>HashMap</tt> 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);
	}

	/**
	* Reconstitutes this map from a stream (that is, deserializes it).
	* @param s the stream
	* @throws ClassNotFoundException if the class of a serialized object
	* could not be found
	* @throws IOException if an I/O error occurs
	*/
	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);

	// Check Map.Entry[].class since it's the nearest public type to
	// what we're actually creating.
	SharedSecrets.getJavaOISAccess().checkArray(s, Map.Entry[].class, cap);
	@SuppressWarnings({"rawtypes","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.
	*/

	// Create a regular (non-tree) node
	Node<K,V> newNode(int hash, K key, V value, Node<K,V> next) {
	return new Node<>(hash, key, value, next);
	}

	// For conversion from TreeNodes to plain nodes
	Node<K,V> replacementNode(Node<K,V> p, Node<K,V> next) {
	return new Node<>(p.hash, p.key, p.value, next);
	}

	// Create a tree bin node
	TreeNode<K,V> newTreeNode(int hash, K key, V value, Node<K,V> next) {
	return new TreeNode<>(hash, key, value, next);
	}

	// For treeifyBin
	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 (int i = 0; i < tab.length; ++i) {
	for (Node<K,V> e = tab[i]; e != null; e = e.next) {
	s.writeObject(e.key);
	s.writeObject(e.value);
	}
	}
	}
	}

	/* ------------------------------------------------------------ */
	// Tree bins

	/**
	* Entry for Tree bins. Extends LinkedHashMap.Entry (which in turn
	* extends Node) so can be used as extension of either regular or
	* linked node.
	*/
	static final class TreeNode<K,V> extends LinkedHashMap.Entry<K,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 && k.equals(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.
	*/
	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 && k.equals(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
	\|\| (movable
	&& (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) ? false : 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) ? false : 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;
	if (tr != null && !checkInvariants(tr))
	return false;
	return true;
	}
	}

	}

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