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<div class="subTitle"><span class="packageLabelInType">Package</span>&nbsp;<a href="package-summary.html">java.util</a></div>
<h2 title="Class HashSet" class="title">Class HashSet&lt;E&gt;</h2>
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<li><a href="../lang/Object.html" title="class in java.lang">java.lang.Object</a></li>
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<li><a href="AbstractCollection.html" title="class in java.util">java.util.AbstractCollection</a>&lt;E&gt;</li>
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<li><a href="AbstractSet.html" title="class in java.util">java.util.AbstractSet</a>&lt;E&gt;</li>
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<li>java.util.HashSet&lt;E&gt;</li>
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<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>E</code> - the type of elements maintained by this set</dd>
<dt>All Implemented Interfaces:</dt>
<dd><code><a href="../io/Serializable.html" title="interface in java.io">Serializable</a></code>, <code><a href="../lang/Cloneable.html" title="interface in java.lang">Cloneable</a></code>, <code><a href="../lang/Iterable.html" title="interface in java.lang">Iterable</a>&lt;E&gt;</code>, <code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;E&gt;</code>, <code><a href="Set.html" title="interface in java.util">Set</a>&lt;E&gt;</code></dd>
<dt>Direct Known Subclasses:</dt>
<dd><code><a href="../../../java.desktop/javax/print/attribute/standard/JobStateReasons.html" title="class in javax.print.attribute.standard">JobStateReasons</a></code>, <code><a href="LinkedHashSet.html" title="class in java.util">LinkedHashSet</a></code></dd>
<pre>public class <span class="typeNameLabel">HashSet&lt;E&gt;</span>
extends <a href="AbstractSet.html" title="class in java.util">AbstractSet</a>&lt;E&gt;
implements <a href="Set.html" title="interface in java.util">Set</a>&lt;E&gt;, <a href="../lang/Cloneable.html" title="interface in java.lang">Cloneable</a>, <a href="../io/Serializable.html" title="interface in java.io">Serializable</a></pre>
<div class="block">This class implements the <code>Set</code> interface, backed by a hash table
 (actually a <code>HashMap</code> instance).  It makes no guarantees as to the
 iteration order of the set; in particular, it does not guarantee that the
 order will remain constant over time.  This class permits the <code>null</code>
 <p>This class offers constant time performance for the basic operations
 (<code>add</code>, <code>remove</code>, <code>contains</code> and <code>size</code>),
 assuming the hash function disperses the elements properly among the
 buckets.  Iterating over this set requires time proportional to the sum of
 the <code>HashSet</code> instance's size (the number of elements) plus the
 "capacity" of the backing <code>HashMap</code> instance (the number of
 buckets).  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><strong>Note that this implementation is not synchronized.</strong>
 If multiple threads access a hash set concurrently, and at least one of
 the threads modifies the set, it <i>must</i> be synchronized externally.
 This is typically accomplished by synchronizing on some object that
 naturally encapsulates the set.
 If no such object exists, the set should be "wrapped" using the
 <a href="Collections.html#synchronizedSet(java.util.Set)"><code>Collections.synchronizedSet</code></a>
 method.  This is best done at creation time, to prevent accidental
 unsynchronized access to the set:<pre>
   Set s = Collections.synchronizedSet(new HashSet(...));</pre>
 <p>The iterators returned by this class's <code>iterator</code> method are
 <i>fail-fast</i>: if the set is modified at any time after the iterator is
 created, in any way except through the iterator's own <code>remove</code>
 method, the Iterator throws a <a href="ConcurrentModificationException.html" title="class in java.util"><code>ConcurrentModificationException</code></a>.
 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 <code>ConcurrentModificationException</code> 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="../../../java.base/java/util/package-summary.html#CollectionsFramework">
 Java Collections Framework</a>.</div>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>1.2</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="Collection.html" title="interface in java.util"><code>Collection</code></a>, 
<a href="Set.html" title="interface in java.util"><code>Set</code></a>, 
<a href="TreeSet.html" title="class in java.util"><code>TreeSet</code></a>, 
<a href="HashMap.html" title="class in java.util"><code>HashMap</code></a>, 
<a href="../../../serialized-form.html#java.util.HashSet">Serialized Form</a></dd>
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<th class="colFirst" scope="col">Constructor</th>
<th class="colLast" scope="col">Description</th>
<tr class="altColor">
<th class="colConstructorName" scope="row"><code><span class="memberNameLink"><a href="#%3Cinit%3E()">HashSet</a></span>()</code></th>
<td class="colLast">
<div class="block">Constructs a new, empty set; the backing <code>HashMap</code> instance has
 default initial capacity (16) and load factor (0.75).</div>
<tr class="rowColor">
<th class="colConstructorName" scope="row"><code><span class="memberNameLink"><a href="#%3Cinit%3E(int)">HashSet</a></span>&#8203;(int&nbsp;initialCapacity)</code></th>
<td class="colLast">
<div class="block">Constructs a new, empty set; the backing <code>HashMap</code> instance has
 the specified initial capacity and default load factor (0.75).</div>
<tr class="altColor">
<th class="colConstructorName" scope="row"><code><span class="memberNameLink"><a href="#%3Cinit%3E(int,float)">HashSet</a></span>&#8203;(int&nbsp;initialCapacity,
       float&nbsp;loadFactor)</code></th>
<td class="colLast">
<div class="block">Constructs a new, empty set; the backing <code>HashMap</code> instance has
 the specified initial capacity and the specified load factor.</div>
<tr class="rowColor">
<th class="colConstructorName" scope="row"><code><span class="memberNameLink"><a href="#%3Cinit%3E(java.util.Collection)">HashSet</a></span>&#8203;(<a href="Collection.html" title="interface in java.util">Collection</a>&lt;? extends <a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;&nbsp;c)</code></th>
<td class="colLast">
<div class="block">Constructs a new set containing the elements in the specified
 collection.</div>
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<th class="colLast" scope="col">Description</th>
<tr class="altColor" id="i0">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#add(E)">add</a></span>&#8203;(<a href="HashSet.html" title="type parameter in HashSet">E</a>&nbsp;e)</code></th>
<td class="colLast">
<div class="block">Adds the specified element to this set if it is not already present.</div>
<tr class="rowColor" id="i1">
<td class="colFirst"><code>void</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#clear()">clear</a></span>()</code></th>
<td class="colLast">
<div class="block">Removes all of the elements from this set.</div>
<tr class="altColor" id="i2">
<td class="colFirst"><code><a href="../lang/Object.html" title="class in java.lang">Object</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#clone()">clone</a></span>()</code></th>
<td class="colLast">
<div class="block">Returns a shallow copy of this <code>HashSet</code> instance: the elements
 themselves are not cloned.</div>
<tr class="rowColor" id="i3">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#contains(java.lang.Object)">contains</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o)</code></th>
<td class="colLast">
<div class="block">Returns <code>true</code> if this set contains the specified element.</div>
<tr class="altColor" id="i4">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#isEmpty()">isEmpty</a></span>()</code></th>
<td class="colLast">
<div class="block">Returns <code>true</code> if this set contains no elements.</div>
<tr class="rowColor" id="i5">
<td class="colFirst"><code><a href="Iterator.html" title="interface in java.util">Iterator</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#iterator()">iterator</a></span>()</code></th>
<td class="colLast">
<div class="block">Returns an iterator over the elements in this set.</div>
<tr class="altColor" id="i6">
<td class="colFirst"><code>boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#remove(java.lang.Object)">remove</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o)</code></th>
<td class="colLast">
<div class="block">Removes the specified element from this set if it is present.</div>
<tr class="rowColor" id="i7">
<td class="colFirst"><code>int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#size()">size</a></span>()</code></th>
<td class="colLast">
<div class="block">Returns the number of elements in this set (its cardinality).</div>
<tr class="altColor" id="i8">
<td class="colFirst"><code><a href="Spliterator.html" title="interface in java.util">Spliterator</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#spliterator()">spliterator</a></span>()</code></th>
<td class="colLast">
<div class="block">Creates a <em><a href="Spliterator.html#binding">late-binding</a></em>
 and <em>fail-fast</em> <a href="Spliterator.html" title="interface in java.util"><code>Spliterator</code></a> over the elements in this
 set.</div>
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<h3>Methods declared in class&nbsp;java.util.<a href="AbstractSet.html" title="class in java.util">AbstractSet</a></h3>
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<h3>Methods declared in interface&nbsp;java.util.<a href="Set.html" title="interface in java.util">Set</a></h3>
<code><a href="Set.html#addAll(java.util.Collection)">addAll</a>, <a href="Set.html#containsAll(java.util.Collection)">containsAll</a>, <a href="Set.html#equals(java.lang.Object)">equals</a>, <a href="Set.html#hashCode()">hashCode</a>, <a href="Set.html#removeAll(java.util.Collection)">removeAll</a>, <a href="Set.html#retainAll(java.util.Collection)">retainAll</a>, <a href="Set.html#toArray()">toArray</a>, <a href="Set.html#toArray(T%5B%5D)">toArray</a></code></li>
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<h4>HashSet</h4>
<pre>public&nbsp;HashSet()</pre>
<div class="block">Constructs a new, empty set; the backing <code>HashMap</code> instance has
 default initial capacity (16) and load factor (0.75).</div>
<a id="&lt;init&gt;(java.util.Collection)">
<ul class="blockList">
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<h4>HashSet</h4>
<pre>public&nbsp;HashSet&#8203;(<a href="Collection.html" title="interface in java.util">Collection</a>&lt;? extends <a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;&nbsp;c)</pre>
<div class="block">Constructs a new set containing the elements in the specified
 collection.  The <code>HashMap</code> is created with default load factor
 (0.75) and an initial capacity sufficient to contain the elements in
 the specified collection.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>c</code> - the collection whose elements are to be placed into this set</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if the specified collection is null</dd>
<a id="&lt;init&gt;(int,float)">
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<h4>HashSet</h4>
<pre>public&nbsp;HashSet&#8203;(int&nbsp;initialCapacity,
               float&nbsp;loadFactor)</pre>
<div class="block">Constructs a new, empty set; the backing <code>HashMap</code> instance has
 the specified initial capacity and the specified load factor.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>initialCapacity</code> - the initial capacity of the hash map</dd>
<dd><code>loadFactor</code> - the load factor of the hash map</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if the initial capacity is less
             than zero, or if the load factor is nonpositive</dd>
<a id="&lt;init&gt;(int)">
<ul class="blockListLast">
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<h4>HashSet</h4>
<pre>public&nbsp;HashSet&#8203;(int&nbsp;initialCapacity)</pre>
<div class="block">Constructs a new, empty set; the backing <code>HashMap</code> instance has
 the specified initial capacity and default load factor (0.75).</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>initialCapacity</code> - the initial capacity of the hash table</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IllegalArgumentException.html" title="class in java.lang">IllegalArgumentException</a></code> - if the initial capacity is less
             than zero</dd>
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<h4>iterator</h4>
<pre class="methodSignature">public&nbsp;<a href="Iterator.html" title="interface in java.util">Iterator</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;&nbsp;iterator()</pre>
<div class="block">Returns an iterator over the elements in this set.  The elements
 are returned in no particular order.</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#iterator()">iterator</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../lang/Iterable.html#iterator()">iterator</a></code>&nbsp;in interface&nbsp;<code><a href="../lang/Iterable.html" title="interface in java.lang">Iterable</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#iterator()">iterator</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="AbstractCollection.html#iterator()">iterator</a></code>&nbsp;in class&nbsp;<code><a href="AbstractCollection.html" title="class in java.util">AbstractCollection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>an Iterator over the elements in this set</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="ConcurrentModificationException.html" title="class in java.util"><code>ConcurrentModificationException</code></a></dd>
<a id="size()">
<ul class="blockList">
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<h4>size</h4>
<pre class="methodSignature">public&nbsp;int&nbsp;size()</pre>
<div class="block">Returns the number of elements in this set (its cardinality).</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#size()">size</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#size()">size</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the number of elements in this set (its cardinality)</dd>
<a id="isEmpty()">
<ul class="blockList">
<li class="blockList">
<h4>isEmpty</h4>
<pre class="methodSignature">public&nbsp;boolean&nbsp;isEmpty()</pre>
<div class="block">Returns <code>true</code> if this set contains no elements.</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#isEmpty()">isEmpty</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#isEmpty()">isEmpty</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Overrides:</span></dt>
<dd><code><a href="AbstractCollection.html#isEmpty()">isEmpty</a></code>&nbsp;in class&nbsp;<code><a href="AbstractCollection.html" title="class in java.util">AbstractCollection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if this set contains no elements</dd>
<a id="contains(java.lang.Object)">
<ul class="blockList">
<li class="blockList">
<h4>contains</h4>
<pre class="methodSignature">public&nbsp;boolean&nbsp;contains&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o)</pre>
<div class="block">Returns <code>true</code> if this set contains the specified element.
 More formally, returns <code>true</code> if and only if this set
 contains an element <code>e</code> such that
 <code>Objects.equals(o, e)</code>.</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#contains(java.lang.Object)">contains</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#contains(java.lang.Object)">contains</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Overrides:</span></dt>
<dd><code><a href="AbstractCollection.html#contains(java.lang.Object)">contains</a></code>&nbsp;in class&nbsp;<code><a href="AbstractCollection.html" title="class in java.util">AbstractCollection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>o</code> - element whose presence in this set is to be tested</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if this set contains the specified element</dd>
<a id="add(java.lang.Object)">
</a><a id="add(E)">
<ul class="blockList">
<li class="blockList">
<h4>add</h4>
<pre class="methodSignature">public&nbsp;boolean&nbsp;add&#8203;(<a href="HashSet.html" title="type parameter in HashSet">E</a>&nbsp;e)</pre>
<div class="block">Adds the specified element to this set if it is not already present.
 More formally, adds the specified element <code>e</code> to this set if
 this set contains no element <code>e2</code> such that
 <code>Objects.equals(e, e2)</code>.
 If this set already contains the element, the call leaves the set
 unchanged and returns <code>false</code>.</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#add(E)">add</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#add(E)">add</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Overrides:</span></dt>
<dd><code><a href="AbstractCollection.html#add(E)">add</a></code>&nbsp;in class&nbsp;<code><a href="AbstractCollection.html" title="class in java.util">AbstractCollection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>e</code> - element to be added to this set</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if this set did not already contain the specified
 element</dd>
<a id="remove(java.lang.Object)">
<ul class="blockList">
<li class="blockList">
<h4>remove</h4>
<pre class="methodSignature">public&nbsp;boolean&nbsp;remove&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o)</pre>
<div class="block">Removes the specified element from this set if it is present.
 More formally, removes an element <code>e</code> such that
 <code>Objects.equals(o, e)</code>,
 if this set contains such an element.  Returns <code>true</code> if
 this set contained the element (or equivalently, if this set
 changed as a result of the call).  (This set will not contain the
 element once the call returns.)</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#remove(java.lang.Object)">remove</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#remove(java.lang.Object)">remove</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Overrides:</span></dt>
<dd><code><a href="AbstractCollection.html#remove(java.lang.Object)">remove</a></code>&nbsp;in class&nbsp;<code><a href="AbstractCollection.html" title="class in java.util">AbstractCollection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>o</code> - object to be removed from this set, if present</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the set contained the specified element</dd>
<a id="clear()">
<ul class="blockList">
<li class="blockList">
<h4>clear</h4>
<pre class="methodSignature">public&nbsp;void&nbsp;clear()</pre>
<div class="block">Removes all of the elements from this set.
 The set will be empty after this call returns.</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#clear()">clear</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#clear()">clear</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Overrides:</span></dt>
<dd><code><a href="AbstractCollection.html#clear()">clear</a></code>&nbsp;in class&nbsp;<code><a href="AbstractCollection.html" title="class in java.util">AbstractCollection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<a id="clone()">
<ul class="blockList">
<li class="blockList">
<h4>clone</h4>
<pre class="methodSignature">public&nbsp;<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;clone()</pre>
<div class="block">Returns a shallow copy of this <code>HashSet</code> instance: the elements
 themselves are not cloned.</div>
<dt><span class="overrideSpecifyLabel">Overrides:</span></dt>
<dd><code><a href="../lang/Object.html#clone()">clone</a></code>&nbsp;in class&nbsp;<code><a href="../lang/Object.html" title="class in java.lang">Object</a></code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>a shallow copy of this set</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="../lang/Cloneable.html" title="interface in java.lang"><code>Cloneable</code></a></dd>
<a id="spliterator()">
<ul class="blockListLast">
<li class="blockList">
<h4>spliterator</h4>
<pre class="methodSignature">public&nbsp;<a href="Spliterator.html" title="interface in java.util">Spliterator</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;&nbsp;spliterator()</pre>
<div class="block">Creates a <em><a href="Spliterator.html#binding">late-binding</a></em>
 and <em>fail-fast</em> <a href="Spliterator.html" title="interface in java.util"><code>Spliterator</code></a> over the elements in this
 <p>The <code>Spliterator</code> reports <a href="Spliterator.html#SIZED"><code>Spliterator.SIZED</code></a> and
 <a href="Spliterator.html#DISTINCT"><code>Spliterator.DISTINCT</code></a>.  Overriding implementations should document
 the reporting of additional characteristic values.</div>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Collection.html#spliterator()">spliterator</a></code>&nbsp;in interface&nbsp;<code><a href="Collection.html" title="interface in java.util">Collection</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../lang/Iterable.html#spliterator()">spliterator</a></code>&nbsp;in interface&nbsp;<code><a href="../lang/Iterable.html" title="interface in java.lang">Iterable</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="Set.html#spliterator()">spliterator</a></code>&nbsp;in interface&nbsp;<code><a href="Set.html" title="interface in java.util">Set</a>&lt;<a href="HashSet.html" title="type parameter in HashSet">E</a>&gt;</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>a <code>Spliterator</code> over the elements in this set</dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>1.8</dd>
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