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	/*
	* Copyright (c) 1997, 2019, 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.util.Map.Entry;

	/**
	* This class provides a skeletal implementation of the {@code Map}
	* interface, to minimize the effort required to implement this interface.
	*
	* <p>To implement an unmodifiable map, the programmer needs only to extend this
	* class and provide an implementation for the {@code entrySet} method, which
	* returns a set-view of the map's mappings. Typically, the returned set
	* will, in turn, be implemented atop {@code AbstractSet}. This set should
	* not support the {@code add} or {@code remove} methods, and its iterator
	* should not support the {@code remove} method.
	*
	* <p>To implement a modifiable map, the programmer must additionally override
	* this class's {@code put} method (which otherwise throws an
	* {@code UnsupportedOperationException}), and the iterator returned by
	* {@code entrySet().iterator()} must additionally implement its
	* {@code remove} method.
	*
	* <p>The programmer should generally provide a void (no argument) and map
	* constructor, as per the recommendation in the {@code Map} interface
	* specification.
	*
	* <p>The documentation for each non-abstract method in this class describes its
	* implementation in detail. Each of these methods may be overridden if the
	* map being implemented admits a more efficient implementation.
	*
	* <p>This class is a member of the
	* <a href="{@docRoot}/java.base/java/util/package-summary.html#CollectionsFramework">
	* Java Collections Framework</a>.
	*
	* @param <K> the type of keys maintained by this map
	* @param <V> the type of mapped values
	*
	* @author Josh Bloch
	* @author Neal Gafter
	* @see Map
	* @see Collection
	* @since 1.2
	*/

	public abstract class AbstractMap<K,V> implements Map<K,V> {
	/**
	* Sole constructor. (For invocation by subclass constructors, typically
	* implicit.)
	*/
	protected AbstractMap() {
	}

	// Query Operations

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation returns {@code entrySet().size()}.
	*/
	public int size() {
	return entrySet().size();
	}

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation returns {@code size() == 0}.
	*/
	public boolean isEmpty() {
	return size() == 0;
	}

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation iterates over {@code entrySet()} searching
	* for an entry with the specified value. If such an entry is found,
	* {@code true} is returned. If the iteration terminates without
	* finding such an entry, {@code false} is returned. Note that this
	* implementation requires linear time in the size of the map.
	*
	* @throws ClassCastException {@inheritDoc}
	* @throws NullPointerException {@inheritDoc}
	*/
	public boolean containsValue(Object value) {
	Iterator<Entry<K,V>> i = entrySet().iterator();
	if (value==null) {
	while (i.hasNext()) {
	Entry<K,V> e = i.next();
	if (e.getValue()==null)
	return true;
	}
	} else {
	while (i.hasNext()) {
	Entry<K,V> e = i.next();
	if (value.equals(e.getValue()))
	return true;
	}
	}
	return false;
	}

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation iterates over {@code entrySet()} searching
	* for an entry with the specified key. If such an entry is found,
	* {@code true} is returned. If the iteration terminates without
	* finding such an entry, {@code false} is returned. Note that this
	* implementation requires linear time in the size of the map; many
	* implementations will override this method.
	*
	* @throws ClassCastException {@inheritDoc}
	* @throws NullPointerException {@inheritDoc}
	*/
	public boolean containsKey(Object key) {
	Iterator<Map.Entry<K,V>> i = entrySet().iterator();
	if (key==null) {
	while (i.hasNext()) {
	Entry<K,V> e = i.next();
	if (e.getKey()==null)
	return true;
	}
	} else {
	while (i.hasNext()) {
	Entry<K,V> e = i.next();
	if (key.equals(e.getKey()))
	return true;
	}
	}
	return false;
	}

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation iterates over {@code entrySet()} searching
	* for an entry with the specified key. If such an entry is found,
	* the entry's value is returned. If the iteration terminates without
	* finding such an entry, {@code null} is returned. Note that this
	* implementation requires linear time in the size of the map; many
	* implementations will override this method.
	*
	* @throws ClassCastException {@inheritDoc}
	* @throws NullPointerException {@inheritDoc}
	*/
	public V get(Object key) {
	Iterator<Entry<K,V>> i = entrySet().iterator();
	if (key==null) {
	while (i.hasNext()) {
	Entry<K,V> e = i.next();
	if (e.getKey()==null)
	return e.getValue();
	}
	} else {
	while (i.hasNext()) {
	Entry<K,V> e = i.next();
	if (key.equals(e.getKey()))
	return e.getValue();
	}
	}
	return null;
	}


	// Modification Operations

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation always throws an
	* {@code UnsupportedOperationException}.
	*
	* @throws UnsupportedOperationException {@inheritDoc}
	* @throws ClassCastException {@inheritDoc}
	* @throws NullPointerException {@inheritDoc}
	* @throws IllegalArgumentException {@inheritDoc}
	*/
	public V put(K key, V value) {
	throw new UnsupportedOperationException();
	}

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation iterates over {@code entrySet()} searching for an
	* entry with the specified key. If such an entry is found, its value is
	* obtained with its {@code getValue} operation, the entry is removed
	* from the collection (and the backing map) with the iterator's
	* {@code remove} operation, and the saved value is returned. If the
	* iteration terminates without finding such an entry, {@code null} is
	* returned. Note that this implementation requires linear time in the
	* size of the map; many implementations will override this method.
	*
	* <p>Note that this implementation throws an
	* {@code UnsupportedOperationException} if the {@code entrySet}
	* iterator does not support the {@code remove} method and this map
	* contains a mapping for the specified key.
	*
	* @throws UnsupportedOperationException {@inheritDoc}
	* @throws ClassCastException {@inheritDoc}
	* @throws NullPointerException {@inheritDoc}
	*/
	public V remove(Object key) {
	Iterator<Entry<K,V>> i = entrySet().iterator();
	Entry<K,V> correctEntry = null;
	if (key==null) {
	while (correctEntry==null && i.hasNext()) {
	Entry<K,V> e = i.next();
	if (e.getKey()==null)
	correctEntry = e;
	}
	} else {
	while (correctEntry==null && i.hasNext()) {
	Entry<K,V> e = i.next();
	if (key.equals(e.getKey()))
	correctEntry = e;
	}
	}

	V oldValue = null;
	if (correctEntry !=null) {
	oldValue = correctEntry.getValue();
	i.remove();
	}
	return oldValue;
	}


	// Bulk Operations

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation iterates over the specified map's
	* {@code entrySet()} collection, and calls this map's {@code put}
	* operation once for each entry returned by the iteration.
	*
	* <p>Note that this implementation throws an
	* {@code UnsupportedOperationException} if this map does not support
	* the {@code put} operation and the specified map is nonempty.
	*
	* @throws UnsupportedOperationException {@inheritDoc}
	* @throws ClassCastException {@inheritDoc}
	* @throws NullPointerException {@inheritDoc}
	* @throws IllegalArgumentException {@inheritDoc}
	*/
	public void putAll(Map<? extends K, ? extends V> m) {
	for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
	put(e.getKey(), e.getValue());
	}

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation calls {@code entrySet().clear()}.
	*
	* <p>Note that this implementation throws an
	* {@code UnsupportedOperationException} if the {@code entrySet}
	* does not support the {@code clear} operation.
	*
	* @throws UnsupportedOperationException {@inheritDoc}
	*/
	public void clear() {
	entrySet().clear();
	}


	// Views

	/**
	* Each of these fields are initialized to contain an instance of the
	* appropriate view the first time this view is requested. The views are
	* stateless, so there's no reason to create more than one of each.
	*
	* <p>Since there is no synchronization performed while accessing these fields,
	* it is expected that java.util.Map view classes using these fields have
	* no non-final fields (or any fields at all except for outer-this). Adhering
	* to this rule would make the races on these fields benign.
	*
	* <p>It is also imperative that implementations read the field only once,
	* as in:
	*
	* <pre> {@code
	* public Set<K> keySet() {
	* Set<K> ks = keySet; // single racy read
	* if (ks == null) {
	* ks = new KeySet();
	* keySet = ks;
	* }
	* return ks;
	* }
	*}</pre>
	*/
	transient Set<K> keySet;
	transient Collection<V> values;

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation returns a set that subclasses {@link AbstractSet}.
	* The subclass's iterator method returns a "wrapper object" over this
	* map's {@code entrySet()} iterator. The {@code size} method
	* delegates to this map's {@code size} method and the
	* {@code contains} method delegates to this map's
	* {@code containsKey} method.
	*
	* <p>The set is created the first time this method is called,
	* and returned in response to all subsequent calls. No synchronization
	* is performed, so there is a slight chance that multiple calls to this
	* method will not all return the same set.
	*/
	public Set<K> keySet() {
	Set<K> ks = keySet;
	if (ks == null) {
	ks = new AbstractSet<K>() {
	public Iterator<K> iterator() {
	return new Iterator<K>() {
	private Iterator<Entry<K,V>> i = entrySet().iterator();

	public boolean hasNext() {
	return i.hasNext();
	}

	public K next() {
	return i.next().getKey();
	}

	public void remove() {
	i.remove();
	}
	};
	}

	public int size() {
	return AbstractMap.this.size();
	}

	public boolean isEmpty() {
	return AbstractMap.this.isEmpty();
	}

	public void clear() {
	AbstractMap.this.clear();
	}

	public boolean contains(Object k) {
	return AbstractMap.this.containsKey(k);
	}
	};
	keySet = ks;
	}
	return ks;
	}

	/**
	* {@inheritDoc}
	*
	* @implSpec
	* This implementation returns a collection that subclasses {@link
	* AbstractCollection}. The subclass's iterator method returns a
	* "wrapper object" over this map's {@code entrySet()} iterator.
	* The {@code size} method delegates to this map's {@code size}
	* method and the {@code contains} method delegates to this map's
	* {@code containsValue} method.
	*
	* <p>The collection is created the first time this method is called, and
	* returned in response to all subsequent calls. No synchronization is
	* performed, so there is a slight chance that multiple calls to this
	* method will not all return the same collection.
	*/
	public Collection<V> values() {
	Collection<V> vals = values;
	if (vals == null) {
	vals = new AbstractCollection<V>() {
	public Iterator<V> iterator() {
	return new Iterator<V>() {
	private Iterator<Entry<K,V>> i = entrySet().iterator();

	public boolean hasNext() {
	return i.hasNext();
	}

	public V next() {
	return i.next().getValue();
	}

	public void remove() {
	i.remove();
	}
	};
	}

	public int size() {
	return AbstractMap.this.size();
	}

	public boolean isEmpty() {
	return AbstractMap.this.isEmpty();
	}

	public void clear() {
	AbstractMap.this.clear();
	}

	public boolean contains(Object v) {
	return AbstractMap.this.containsValue(v);
	}
	};
	values = vals;
	}
	return vals;
	}

	public abstract Set<Entry<K,V>> entrySet();


	// Comparison and hashing

	/**
	* Compares the specified object with this map for equality. Returns
	* {@code true} if the given object is also a map and the two maps
	* represent the same mappings. More formally, two maps {@code m1} and
	* {@code m2} represent the same mappings if
	* {@code m1.entrySet().equals(m2.entrySet())}. This ensures that the
	* {@code equals} method works properly across different implementations
	* of the {@code Map} interface.
	*
	* @implSpec
	* This implementation first checks if the specified object is this map;
	* if so it returns {@code true}. Then, it checks if the specified
	* object is a map whose size is identical to the size of this map; if
	* not, it returns {@code false}. If so, it iterates over this map's
	* {@code entrySet} collection, and checks that the specified map
	* contains each mapping that this map contains. If the specified map
	* fails to contain such a mapping, {@code false} is returned. If the
	* iteration completes, {@code true} is returned.
	*
	* @param o object to be compared for equality with this map
	* @return {@code true} if the specified object is equal to this map
	*/
	public boolean equals(Object o) {
	if (o == this)
	return true;

	if (!(o instanceof Map<?, ?> m))
	return false;
	if (m.size() != size())
	return false;

	try {
	for (Entry<K, V> e : entrySet()) {
	K key = e.getKey();
	V value = e.getValue();
	if (value == null) {
	if (!(m.get(key) == null && m.containsKey(key)))
	return false;
	} else {
	if (!value.equals(m.get(key)))
	return false;
	}
	}
	} catch (ClassCastException unused) {
	return false;
	} catch (NullPointerException unused) {
	return false;
	}

	return true;
	}

	/**
	* Returns the hash code value for this map. The hash code of a map is
	* defined to be the sum of the hash codes of each entry in the map's
	* {@code entrySet()} view. This ensures that {@code m1.equals(m2)}
	* implies that {@code m1.hashCode()==m2.hashCode()} for any two maps
	* {@code m1} and {@code m2}, as required by the general contract of
	* {@link Object#hashCode}.
	*
	* @implSpec
	* This implementation iterates over {@code entrySet()}, calling
	* {@link Map.Entry#hashCode hashCode()} on each element (entry) in the
	* set, and adding up the results.
	*
	* @return the hash code value for this map
	* @see Map.Entry#hashCode()
	* @see Object#equals(Object)
	* @see Set#equals(Object)
	*/
	public int hashCode() {
	int h = 0;
	for (Entry<K, V> entry : entrySet())
	h += entry.hashCode();
	return h;
	}

	/**
	* Returns a string representation of this map. The string representation
	* consists of a list of key-value mappings in the order returned by the
	* map's {@code entrySet} view's iterator, enclosed in braces
	* ({@code "{}"}). Adjacent mappings are separated by the characters
	* {@code ", "} (comma and space). Each key-value mapping is rendered as
	* the key followed by an equals sign ({@code "="}) followed by the
	* associated value. Keys and values are converted to strings as by
	* {@link String#valueOf(Object)}.
	*
	* @return a string representation of this map
	*/
	public String toString() {
	Iterator<Entry<K,V>> i = entrySet().iterator();
	if (! i.hasNext())
	return "{}";

	StringBuilder sb = new StringBuilder();
	sb.append('{');
	for (;;) {
	Entry<K,V> e = i.next();
	K key = e.getKey();
	V value = e.getValue();
	sb.append(key == this ? "(this Map)" : key);
	sb.append('=');
	sb.append(value == this ? "(this Map)" : value);
	if (! i.hasNext())
	return sb.append('}').toString();
	sb.append(',').append(' ');
	}
	}

	/**
	* Returns a shallow copy of this {@code AbstractMap} instance: the keys
	* and values themselves are not cloned.
	*
	* @return a shallow copy of this map
	*/
	protected Object clone() throws CloneNotSupportedException {
	AbstractMap<?,?> result = (AbstractMap<?,?>)super.clone();
	result.keySet = null;
	result.values = null;
	return result;
	}

	/**
	* Utility method for SimpleEntry and SimpleImmutableEntry.
	* Test for equality, checking for nulls.
	*
	* NB: Do not replace with Object.equals until JDK-8015417 is resolved.
	*/
	private static boolean eq(Object o1, Object o2) {
	return o1 == null ? o2 == null : o1.equals(o2);
	}

	// Implementation Note: SimpleEntry and SimpleImmutableEntry
	// are distinct unrelated classes, even though they share
	// some code. Since you can't add or subtract final-ness
	// of a field in a subclass, they can't share representations,
	// and the amount of duplicated code is too small to warrant
	// exposing a common abstract class.


	/**
	* An Entry maintaining a key and a value. The value may be
	* changed using the {@code setValue} method. Instances of
	* this class are not associated with any map's entry-set view.
	*
	* @apiNote
	* This class facilitates the process of building custom map
	* implementations. For example, it may be convenient to return
	* arrays of {@code SimpleEntry} instances in method
	* {@code Map.entrySet().toArray}.
	*
	* @since 1.6
	*/
	public static class SimpleEntry<K,V>
	implements Entry<K,V>, java.io.Serializable
	{
	@java.io.Serial
	private static final long serialVersionUID = -8499721149061103585L;

	@SuppressWarnings("serial") // Conditionally serializable
	private final K key;
	@SuppressWarnings("serial") // Conditionally serializable
	private V value;

	/**
	* Creates an entry representing a mapping from the specified
	* key to the specified value.
	*
	* @param key the key represented by this entry
	* @param value the value represented by this entry
	*/
	public SimpleEntry(K key, V value) {
	this.key = key;
	this.value = value;
	}

	/**
	* Creates an entry representing the same mapping as the
	* specified entry.
	*
	* @param entry the entry to copy
	*/
	public SimpleEntry(Entry<? extends K, ? extends V> entry) {
	this.key = entry.getKey();
	this.value = entry.getValue();
	}

	/**
	* Returns the key corresponding to this entry.
	*
	* @return the key corresponding to this entry
	*/
	public K getKey() {
	return key;
	}

	/**
	* Returns the value corresponding to this entry.
	*
	* @return the value corresponding to this entry
	*/
	public V getValue() {
	return value;
	}

	/**
	* Replaces the value corresponding to this entry with the specified
	* value.
	*
	* @param value new value to be stored in this entry
	* @return the old value corresponding to the entry
	*/
	public V setValue(V value) {
	V oldValue = this.value;
	this.value = value;
	return oldValue;
	}

	/**
	* Compares the specified object with this entry for equality.
	* Returns {@code true} if the given object is also a map entry and
	* the two entries represent the same mapping. More formally, two
	* entries {@code e1} and {@code e2} represent the same mapping
	* if<pre>
	* (e1.getKey()==null ?
	* e2.getKey()==null :
	* e1.getKey().equals(e2.getKey()))
	* &&
	* (e1.getValue()==null ?
	* e2.getValue()==null :
	* e1.getValue().equals(e2.getValue()))</pre>
	* This ensures that the {@code equals} method works properly across
	* different implementations of the {@code Map.Entry} interface.
	*
	* @param o object to be compared for equality with this map entry
	* @return {@code true} if the specified object is equal to this map
	* entry
	* @see #hashCode
	*/
	public boolean equals(Object o) {
	return o instanceof Map.Entry<?, ?> e
	&& eq(key, e.getKey())
	&& eq(value, e.getValue());
	}

	/**
	* Returns the hash code value for this map entry. The hash code
	* of a map entry {@code e} is defined to be: <pre>
	* (e.getKey()==null ? 0 : e.getKey().hashCode()) ^
	* (e.getValue()==null ? 0 : e.getValue().hashCode())</pre>
	* This ensures that {@code e1.equals(e2)} implies that
	* {@code e1.hashCode()==e2.hashCode()} for any two Entries
	* {@code e1} and {@code e2}, as required by the general
	* contract of {@link Object#hashCode}.
	*
	* @return the hash code value for this map entry
	* @see #equals
	*/
	public int hashCode() {
	return (key == null ? 0 : key.hashCode()) ^
	(value == null ? 0 : value.hashCode());
	}

	/**
	* Returns a String representation of this map entry. This
	* implementation returns the string representation of this
	* entry's key followed by the equals character ("{@code =}")
	* followed by the string representation of this entry's value.
	*
	* @return a String representation of this map entry
	*/
	public String toString() {
	return key + "=" + value;
	}

	}

	/**
	* An unmodifiable Entry maintaining a key and a value. This class
	* does not support the {@code setValue} method. Instances of
	* this class are not associated with any map's entry-set view.
	*
	* @apiNote
	* Instances of this class are not necessarily immutable, as the key
	* and value may be mutable. An instance of <i>this specific class</i>
	* is unmodifiable, because the key and value references cannot be
	* changed. A reference of this <i>type</i> may not be unmodifiable,
	* as a subclass may be modifiable or may provide the appearance of modifiability.
	* <p>
	* This class may be convenient in methods that return thread-safe snapshots of
	* key-value mappings. For alternatives, see the
	* {@link Map#entry Map::entry} and {@link Map.Entry#copyOf Map.Entry::copyOf}
	* methods.
	*
	* @since 1.6
	*/
	public static class SimpleImmutableEntry<K,V>
	implements Entry<K,V>, java.io.Serializable
	{
	@java.io.Serial
	private static final long serialVersionUID = 7138329143949025153L;

	@SuppressWarnings("serial") // Not statically typed as Serializable
	private final K key;
	@SuppressWarnings("serial") // Not statically typed as Serializable
	private final V value;

	/**
	* Creates an entry representing a mapping from the specified
	* key to the specified value.
	*
	* @param key the key represented by this entry
	* @param value the value represented by this entry
	*/
	public SimpleImmutableEntry(K key, V value) {
	this.key = key;
	this.value = value;
	}

	/**
	* Creates an entry representing the same mapping as the
	* specified entry.
	*
	* @param entry the entry to copy
	*/
	public SimpleImmutableEntry(Entry<? extends K, ? extends V> entry) {
	this.key = entry.getKey();
	this.value = entry.getValue();
	}

	/**
	* Returns the key corresponding to this entry.
	*
	* @return the key corresponding to this entry
	*/
	public K getKey() {
	return key;
	}

	/**
	* Returns the value corresponding to this entry.
	*
	* @return the value corresponding to this entry
	*/
	public V getValue() {
	return value;
	}

	/**
	* Replaces the value corresponding to this entry with the specified
	* value (optional operation). This implementation simply throws
	* {@code UnsupportedOperationException}, as this class implements
	* an unmodifiable map entry.
	*
	* @implSpec
	* The implementation in this class always throws {@code UnsupportedOperationException}.
	*
	* @param value new value to be stored in this entry
	* @return (Does not return)
	* @throws UnsupportedOperationException always
	*/
	public V setValue(V value) {
	throw new UnsupportedOperationException();
	}

	/**
	* Compares the specified object with this entry for equality.
	* Returns {@code true} if the given object is also a map entry and
	* the two entries represent the same mapping. More formally, two
	* entries {@code e1} and {@code e2} represent the same mapping
	* if<pre>
	* (e1.getKey()==null ?
	* e2.getKey()==null :
	* e1.getKey().equals(e2.getKey()))
	* &&
	* (e1.getValue()==null ?
	* e2.getValue()==null :
	* e1.getValue().equals(e2.getValue()))</pre>
	* This ensures that the {@code equals} method works properly across
	* different implementations of the {@code Map.Entry} interface.
	*
	* @param o object to be compared for equality with this map entry
	* @return {@code true} if the specified object is equal to this map
	* entry
	* @see #hashCode
	*/
	public boolean equals(Object o) {
	return o instanceof Map.Entry<?, ?> e
	&& eq(key, e.getKey())
	&& eq(value, e.getValue());
	}

	/**
	* Returns the hash code value for this map entry. The hash code
	* of a map entry {@code e} is defined to be: <pre>
	* (e.getKey()==null ? 0 : e.getKey().hashCode()) ^
	* (e.getValue()==null ? 0 : e.getValue().hashCode())</pre>
	* This ensures that {@code e1.equals(e2)} implies that
	* {@code e1.hashCode()==e2.hashCode()} for any two Entries
	* {@code e1} and {@code e2}, as required by the general
	* contract of {@link Object#hashCode}.
	*
	* @return the hash code value for this map entry
	* @see #equals
	*/
	public int hashCode() {
	return (key == null ? 0 : key.hashCode()) ^
	(value == null ? 0 : value.hashCode());
	}

	/**
	* Returns a String representation of this map entry. This
	* implementation returns the string representation of this
	* entry's key followed by the equals character ("{@code =}")
	* followed by the string representation of this entry's value.
	*
	* @return a String representation of this map entry
	*/
	public String toString() {
	return key + "=" + value;
	}

	}

	}

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