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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 Objects" class="title">Class Objects</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>java.util.Objects</li>
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<pre>public final class <span class="typeNameLabel">Objects</span>
extends <a href="../lang/Object.html" title="class in java.lang">Object</a></pre>
<div class="block">This class consists of <code>static</code> utility methods for operating
 on objects, or checking certain conditions before operation.  These utilities
 include <code>null</code>-safe or <code>null</code>-tolerant methods for computing the
 hash code of an object, returning a string for an object, comparing two
 objects, and checking if indexes or sub-range values are out of bounds.</div>
<dt><span class="simpleTagLabel">API Note:</span></dt>
<dd>Static methods such as <a href="#checkIndex(int,int)"><code>checkIndex(int, int)</code></a>,
 <a href="#checkFromToIndex(int,int,int)"><code>checkFromToIndex(int, int, int)</code></a>, and <a href="#checkFromIndexSize(int,int,int)"><code>checkFromIndexSize(int, int, int)</code></a> are
 provided for the convenience of checking if values corresponding to indexes
 and sub-ranges are out of bounds.
 Variations of these static methods support customization of the runtime
 exception, and corresponding exception detail message, that is thrown when
 values are out of bounds.  Such methods accept a functional interface
 argument, instances of <code>BiFunction</code>, that maps out-of-bound values to a
 runtime exception.  Care should be taken when using such methods in
 combination with an argument that is a lambda expression, method reference or
 class that capture values.  In such cases the cost of capture, related to
 functional interface allocation, may exceed the cost of checking bounds.</dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>1.7</dd>
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<div role="tablist" aria-orientation="horizontal"><button role="tab" aria-selected="true" aria-controls="memberSummary_tabpanel" tabindex="0" onkeydown="switchTab(event)" id="t0" class="activeTableTab">All Methods</button><button role="tab" aria-selected="false" aria-controls="memberSummary_tabpanel" tabindex="-1" onkeydown="switchTab(event)" id="t1" class="tableTab" onclick="show(1);">Static Methods</button><button role="tab" aria-selected="false" aria-controls="memberSummary_tabpanel" tabindex="-1" onkeydown="switchTab(event)" id="t4" class="tableTab" onclick="show(8);">Concrete Methods</button></div>
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<table aria-labelledby="t0">
<th class="colFirst" scope="col">Modifier and Type</th>
<th class="colSecond" scope="col">Method</th>
<th class="colLast" scope="col">Description</th>
<tr class="altColor" id="i0">
<td class="colFirst"><code>static int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#checkFromIndexSize(int,int,int)">checkFromIndexSize</a></span>&#8203;(int&nbsp;fromIndex,
                  int&nbsp;size,
                  int&nbsp;length)</code></th>
<td class="colLast">
<div class="block">Checks if the sub-range from <code>fromIndex</code> (inclusive) to
 <code>fromIndex + size</code> (exclusive) is within the bounds of range from
 <code>0</code> (inclusive) to <code>length</code> (exclusive).</div>
<tr class="rowColor" id="i1">
<td class="colFirst"><code>static int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#checkFromToIndex(int,int,int)">checkFromToIndex</a></span>&#8203;(int&nbsp;fromIndex,
                int&nbsp;toIndex,
                int&nbsp;length)</code></th>
<td class="colLast">
<div class="block">Checks if the sub-range from <code>fromIndex</code> (inclusive) to
 <code>toIndex</code> (exclusive) is within the bounds of range from <code>0</code>
 (inclusive) to <code>length</code> (exclusive).</div>
<tr class="altColor" id="i2">
<td class="colFirst"><code>static int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#checkIndex(int,int)">checkIndex</a></span>&#8203;(int&nbsp;index,
          int&nbsp;length)</code></th>
<td class="colLast">
<div class="block">Checks if the <code>index</code> is within the bounds of the range from
 <code>0</code> (inclusive) to <code>length</code> (exclusive).</div>
<tr class="rowColor" id="i3">
<td class="colFirst"><code>static &lt;T&gt;&nbsp;int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#compare(T,T,java.util.Comparator)">compare</a></span>&#8203;(T&nbsp;a,
       T&nbsp;b,
       <a href="Comparator.html" title="interface in java.util">Comparator</a>&lt;? super T&gt;&nbsp;c)</code></th>
<td class="colLast">
<div class="block">Returns 0 if the arguments are identical and <code>
 c.compare(a, b)</code> otherwise.</div>
<tr class="altColor" id="i4">
<td class="colFirst"><code>static boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#deepEquals(java.lang.Object,java.lang.Object)">deepEquals</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;a,
          <a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;b)</code></th>
<td class="colLast">
<div class="block">Returns <code>true</code> if the arguments are deeply equal to each other
 and <code>false</code> otherwise.</div>
<tr class="rowColor" id="i5">
<td class="colFirst"><code>static boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#equals(java.lang.Object,java.lang.Object)">equals</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;a,
      <a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;b)</code></th>
<td class="colLast">
<div class="block">Returns <code>true</code> if the arguments are equal to each other
 and <code>false</code> otherwise.</div>
<tr class="altColor" id="i6">
<td class="colFirst"><code>static int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#hash(java.lang.Object...)">hash</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>...&nbsp;values)</code></th>
<td class="colLast">
<div class="block">Generates a hash code for a sequence of input values.</div>
<tr class="rowColor" id="i7">
<td class="colFirst"><code>static int</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#hashCode(java.lang.Object)">hashCode</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 the hash code of a non-<code>null</code> argument and 0 for
 a <code>null</code> argument.</div>
<tr class="altColor" id="i8">
<td class="colFirst"><code>static boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#isNull(java.lang.Object)">isNull</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;obj)</code></th>
<td class="colLast">
<div class="block">Returns <code>true</code> if the provided reference is <code>null</code> otherwise
 returns <code>false</code>.</div>
<tr class="rowColor" id="i9">
<td class="colFirst"><code>static boolean</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#nonNull(java.lang.Object)">nonNull</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;obj)</code></th>
<td class="colLast">
<div class="block">Returns <code>true</code> if the provided reference is non-<code>null</code>
 otherwise returns <code>false</code>.</div>
<tr class="altColor" id="i10">
<td class="colFirst"><code>static &lt;T&gt;&nbsp;T</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#requireNonNull(T)">requireNonNull</a></span>&#8203;(T&nbsp;obj)</code></th>
<td class="colLast">
<div class="block">Checks that the specified object reference is not <code>null</code>.</div>
<tr class="rowColor" id="i11">
<td class="colFirst"><code>static &lt;T&gt;&nbsp;T</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#requireNonNull(T,java.lang.String)">requireNonNull</a></span>&#8203;(T&nbsp;obj,
              <a href="../lang/String.html" title="class in java.lang">String</a>&nbsp;message)</code></th>
<td class="colLast">
<div class="block">Checks that the specified object reference is not <code>null</code> and
 throws a customized <a href="../lang/NullPointerException.html" title="class in java.lang"><code>NullPointerException</code></a> if it is.</div>
<tr class="altColor" id="i12">
<td class="colFirst"><code>static &lt;T&gt;&nbsp;T</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#requireNonNull(T,java.util.function.Supplier)">requireNonNull</a></span>&#8203;(T&nbsp;obj,
              <a href="function/Supplier.html" title="interface in java.util.function">Supplier</a>&lt;<a href="../lang/String.html" title="class in java.lang">String</a>&gt;&nbsp;messageSupplier)</code></th>
<td class="colLast">
<div class="block">Checks that the specified object reference is not <code>null</code> and
 throws a customized <a href="../lang/NullPointerException.html" title="class in java.lang"><code>NullPointerException</code></a> if it is.</div>
<tr class="rowColor" id="i13">
<td class="colFirst"><code>static &lt;T&gt;&nbsp;T</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#requireNonNullElse(T,T)">requireNonNullElse</a></span>&#8203;(T&nbsp;obj,
                  T&nbsp;defaultObj)</code></th>
<td class="colLast">
<div class="block">Returns the first argument if it is non-<code>null</code> and
 otherwise returns the non-<code>null</code> second argument.</div>
<tr class="altColor" id="i14">
<td class="colFirst"><code>static &lt;T&gt;&nbsp;T</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#requireNonNullElseGet(T,java.util.function.Supplier)">requireNonNullElseGet</a></span>&#8203;(T&nbsp;obj,
                     <a href="function/Supplier.html" title="interface in java.util.function">Supplier</a>&lt;? extends T&gt;&nbsp;supplier)</code></th>
<td class="colLast">
<div class="block">Returns the first argument if it is non-<code>null</code> and otherwise
 returns the non-<code>null</code> value of <code>supplier.get()</code>.</div>
<tr class="rowColor" id="i15">
<td class="colFirst"><code>static <a href="../lang/String.html" title="class in java.lang">String</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#toString(java.lang.Object)">toString</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 the result of calling <code>toString</code> for a non-<code>
 null</code> argument and <code>"null"</code> for a <code>null</code> argument.</div>
<tr class="altColor" id="i16">
<td class="colFirst"><code>static <a href="../lang/String.html" title="class in java.lang">String</a></code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#toString(java.lang.Object,java.lang.String)">toString</a></span>&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o,
        <a href="../lang/String.html" title="class in java.lang">String</a>&nbsp;nullDefault)</code></th>
<td class="colLast">
<div class="block">Returns the result of calling <code>toString</code> on the first
 argument if the first argument is not <code>null</code> and returns
 the second argument otherwise.</div>
<ul class="blockList">
<li class="blockList"><a id="methods.inherited.from.class.java.lang.Object">
<h3>Methods declared in class&nbsp;java.lang.<a href="../lang/Object.html" title="class in java.lang">Object</a></h3>
<code><a href="../lang/Object.html#clone()">clone</a>, <a href="../lang/Object.html#equals(java.lang.Object)">equals</a>, <a href="../lang/Object.html#finalize()">finalize</a>, <a href="../lang/Object.html#getClass()">getClass</a>, <a href="../lang/Object.html#hashCode()">hashCode</a>, <a href="../lang/Object.html#notify()">notify</a>, <a href="../lang/Object.html#notifyAll()">notifyAll</a>, <a href="../lang/Object.html#toString()">toString</a>, <a href="../lang/Object.html#wait()">wait</a>, <a href="../lang/Object.html#wait(long)">wait</a>, <a href="../lang/Object.html#wait(long,int)">wait</a></code></li>
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<h3>Method Detail</h3>
<a id="equals(java.lang.Object,java.lang.Object)">
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<h4>equals</h4>
<pre class="methodSignature">public static&nbsp;boolean&nbsp;equals&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;a,
                             <a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;b)</pre>
<div class="block">Returns <code>true</code> if the arguments are equal to each other
 and <code>false</code> otherwise.
 Consequently, if both arguments are <code>null</code>, <code>true</code>
 is returned and if exactly one argument is <code>null</code>, <code>
 false</code> is returned.  Otherwise, equality is determined by using
 the <a href="../lang/Object.html#equals(java.lang.Object)"><code>equals</code></a> method of the first
 argument.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>a</code> - an object</dd>
<dd><code>b</code> - an object to be compared with <code>a</code> for equality</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the arguments are equal to each other
 and <code>false</code> otherwise</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="../lang/Object.html#equals(java.lang.Object)"><code>Object.equals(Object)</code></a></dd>
<a id="deepEquals(java.lang.Object,java.lang.Object)">
<ul class="blockList">
<li class="blockList">
<h4>deepEquals</h4>
<pre class="methodSignature">public static&nbsp;boolean&nbsp;deepEquals&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;a,
                                 <a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;b)</pre>
<div class="block">Returns <code>true</code> if the arguments are deeply equal to each other
 and <code>false</code> otherwise.
 Two <code>null</code> values are deeply equal.  If both arguments are
 arrays, the algorithm in <a href="Arrays.html#deepEquals(java.lang.Object%5B%5D,java.lang.Object%5B%5D)"><code>Arrays.deepEquals</code></a> is used to determine equality.
 Otherwise, equality is determined by using the <a href="../lang/Object.html#equals(java.lang.Object)"><code>equals</code></a> method of the first argument.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>a</code> - an object</dd>
<dd><code>b</code> - an object to be compared with <code>a</code> for deep equality</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the arguments are deeply equal to each other
 and <code>false</code> otherwise</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="Arrays.html#deepEquals(java.lang.Object%5B%5D,java.lang.Object%5B%5D)"><code>Arrays.deepEquals(Object[], Object[])</code></a>, 
<a href="#equals(java.lang.Object,java.lang.Object)"><code>equals(Object, Object)</code></a></dd>
<a id="hashCode(java.lang.Object)">
<ul class="blockList">
<li class="blockList">
<h4>hashCode</h4>
<pre class="methodSignature">public static&nbsp;int&nbsp;hashCode&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o)</pre>
<div class="block">Returns the hash code of a non-<code>null</code> argument and 0 for
 a <code>null</code> argument.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>o</code> - an object</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the hash code of a non-<code>null</code> argument and 0 for
 a <code>null</code> argument</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="../lang/Object.html#hashCode()"><code>Object.hashCode()</code></a></dd>
<a id="hash(java.lang.Object...)">
<ul class="blockList">
<li class="blockList">
<h4>hash</h4>
<pre class="methodSignature">public static&nbsp;int&nbsp;hash&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>...&nbsp;values)</pre>
<div class="block">Generates a hash code for a sequence of input values. The hash
 code is generated as if all the input values were placed into an
 array, and that array were hashed by calling <a href="Arrays.html#hashCode(java.lang.Object%5B%5D)"><code>Arrays.hashCode(Object[])</code></a>.
 <p>This method is useful for implementing <a href="../lang/Object.html#hashCode()"><code>Object.hashCode()</code></a> on objects containing multiple fields. For
 example, if an object that has three fields, <code>x</code>, <code>
 y</code>, and <code>z</code>, one could write:
 <blockquote><pre>
 &#064;Override public int hashCode() {
     return Objects.hash(x, y, z);
 </pre></blockquote>
 <b>Warning: When a single object reference is supplied, the returned
 value does not equal the hash code of that object reference.</b> This
 value can be computed by calling <a href="#hashCode(java.lang.Object)"><code>hashCode(Object)</code></a>.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>values</code> - the values to be hashed</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>a hash value of the sequence of input values</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="Arrays.html#hashCode(java.lang.Object%5B%5D)"><code>Arrays.hashCode(Object[])</code></a>, 
<a href="List.html#hashCode()"><code>List.hashCode()</code></a></dd>
<a id="toString(java.lang.Object)">
<ul class="blockList">
<li class="blockList">
<h4>toString</h4>
<pre class="methodSignature">public static&nbsp;<a href="../lang/String.html" title="class in java.lang">String</a>&nbsp;toString&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o)</pre>
<div class="block">Returns the result of calling <code>toString</code> for a non-<code>
 null</code> argument and <code>"null"</code> for a <code>null</code> argument.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>o</code> - an object</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the result of calling <code>toString</code> for a non-<code>
 null</code> argument and <code>"null"</code> for a <code>null</code> argument</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="../lang/Object.html#toString()"><code>Object.toString()</code></a>, 
<a href="../lang/String.html#valueOf(java.lang.Object)"><code>String.valueOf(Object)</code></a></dd>
<a id="toString(java.lang.Object,java.lang.String)">
<ul class="blockList">
<li class="blockList">
<h4>toString</h4>
<pre class="methodSignature">public static&nbsp;<a href="../lang/String.html" title="class in java.lang">String</a>&nbsp;toString&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;o,
                              <a href="../lang/String.html" title="class in java.lang">String</a>&nbsp;nullDefault)</pre>
<div class="block">Returns the result of calling <code>toString</code> on the first
 argument if the first argument is not <code>null</code> and returns
 the second argument otherwise.</div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>o</code> - an object</dd>
<dd><code>nullDefault</code> - string to return if the first argument is
        <code>null</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the result of calling <code>toString</code> on the first
 argument if it is not <code>null</code> and the second argument
 otherwise.</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="#toString(java.lang.Object)"><code>toString(Object)</code></a></dd>
<a id="compare(java.lang.Object,java.lang.Object,java.util.Comparator)">
</a><a id="compare(T,T,java.util.Comparator)">
<ul class="blockList">
<li class="blockList">
<h4>compare</h4>
<pre class="methodSignature">public static&nbsp;&lt;T&gt;&nbsp;int&nbsp;compare&#8203;(T&nbsp;a,
                              T&nbsp;b,
                              <a href="Comparator.html" title="interface in java.util">Comparator</a>&lt;? super T&gt;&nbsp;c)</pre>
<div class="block">Returns 0 if the arguments are identical and <code>
 c.compare(a, b)</code> otherwise.
 Consequently, if both arguments are <code>null</code> 0
 is returned.
 <p>Note that if one of the arguments is <code>null</code>, a <code>
 NullPointerException</code> may or may not be thrown depending on
 what ordering policy, if any, the <a href="Comparator.html" title="interface in java.util"><code>Comparator</code></a>
 chooses to have for <code>null</code> values.</div>
<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>T</code> - the type of the objects being compared</dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>a</code> - an object</dd>
<dd><code>b</code> - an object to be compared with <code>a</code></dd>
<dd><code>c</code> - the <code>Comparator</code> to compare the first two arguments</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>0 if the arguments are identical and <code>
 c.compare(a, b)</code> otherwise.</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="../lang/Comparable.html" title="interface in java.lang"><code>Comparable</code></a>, 
<a href="Comparator.html" title="interface in java.util"><code>Comparator</code></a></dd>
<a id="requireNonNull(java.lang.Object)">
</a><a id="requireNonNull(T)">
<ul class="blockList">
<li class="blockList">
<h4>requireNonNull</h4>
<pre class="methodSignature">public static&nbsp;&lt;T&gt;&nbsp;T&nbsp;requireNonNull&#8203;(T&nbsp;obj)</pre>
<div class="block">Checks that the specified object reference is not <code>null</code>. This
 method is designed primarily for doing parameter validation in methods
 and constructors, as demonstrated below:
 <blockquote><pre>
 public Foo(Bar bar) {
     this.bar = Objects.requireNonNull(bar);
 </pre></blockquote></div>
<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>T</code> - the type of the reference</dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>obj</code> - the object reference to check for nullity</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>obj</code> if not <code>null</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if <code>obj</code> is <code>null</code></dd>
<a id="requireNonNull(java.lang.Object,java.lang.String)">
</a><a id="requireNonNull(T,java.lang.String)">
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<li class="blockList">
<h4>requireNonNull</h4>
<pre class="methodSignature">public static&nbsp;&lt;T&gt;&nbsp;T&nbsp;requireNonNull&#8203;(T&nbsp;obj,
                                   <a href="../lang/String.html" title="class in java.lang">String</a>&nbsp;message)</pre>
<div class="block">Checks that the specified object reference is not <code>null</code> and
 throws a customized <a href="../lang/NullPointerException.html" title="class in java.lang"><code>NullPointerException</code></a> if it is. This method
 is designed primarily for doing parameter validation in methods and
 constructors with multiple parameters, as demonstrated below:
 <blockquote><pre>
 public Foo(Bar bar, Baz baz) {
     this.bar = Objects.requireNonNull(bar, "bar must not be null");
     this.baz = Objects.requireNonNull(baz, "baz must not be null");
 </pre></blockquote></div>
<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>T</code> - the type of the reference</dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>obj</code> - the object reference to check for nullity</dd>
<dd><code>message</code> - detail message to be used in the event that a <code>
                NullPointerException</code> is thrown</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>obj</code> if not <code>null</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if <code>obj</code> is <code>null</code></dd>
<a id="isNull(java.lang.Object)">
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<li class="blockList">
<h4>isNull</h4>
<pre class="methodSignature">public static&nbsp;boolean&nbsp;isNull&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;obj)</pre>
<div class="block">Returns <code>true</code> if the provided reference is <code>null</code> otherwise
 returns <code>false</code>.</div>
<dt><span class="simpleTagLabel">API Note:</span></dt>
<dd>This method exists to be used as a
 <a href="function/Predicate.html" title="interface in java.util.function"><code>Predicate</code></a>, <code>filter(Objects::isNull)</code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>obj</code> - a reference to be checked against <code>null</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the provided reference is <code>null</code> otherwise
 <code>false</code></dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>1.8</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="function/Predicate.html" title="interface in java.util.function"><code>Predicate</code></a></dd>
<a id="nonNull(java.lang.Object)">
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<li class="blockList">
<h4>nonNull</h4>
<pre class="methodSignature">public static&nbsp;boolean&nbsp;nonNull&#8203;(<a href="../lang/Object.html" title="class in java.lang">Object</a>&nbsp;obj)</pre>
<div class="block">Returns <code>true</code> if the provided reference is non-<code>null</code>
 otherwise returns <code>false</code>.</div>
<dt><span class="simpleTagLabel">API Note:</span></dt>
<dd>This method exists to be used as a
 <a href="function/Predicate.html" title="interface in java.util.function"><code>Predicate</code></a>, <code>filter(Objects::nonNull)</code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>obj</code> - a reference to be checked against <code>null</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>true</code> if the provided reference is non-<code>null</code>
 otherwise <code>false</code></dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>1.8</dd>
<dt><span class="seeLabel">See Also:</span></dt>
<dd><a href="function/Predicate.html" title="interface in java.util.function"><code>Predicate</code></a></dd>
<a id="requireNonNullElse(java.lang.Object,java.lang.Object)">
</a><a id="requireNonNullElse(T,T)">
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<li class="blockList">
<h4>requireNonNullElse</h4>
<pre class="methodSignature">public static&nbsp;&lt;T&gt;&nbsp;T&nbsp;requireNonNullElse&#8203;(T&nbsp;obj,
                                       T&nbsp;defaultObj)</pre>
<div class="block">Returns the first argument if it is non-<code>null</code> and
 otherwise returns the non-<code>null</code> second argument.</div>
<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>T</code> - the type of the reference</dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>obj</code> - an object</dd>
<dd><code>defaultObj</code> - a non-<code>null</code> object to return if the first argument
                   is <code>null</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the first argument if it is non-<code>null</code> and
        otherwise the second argument if it is non-<code>null</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if both <code>obj</code> is null and
        <code>defaultObj</code> is <code>null</code></dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<a id="requireNonNullElseGet(java.lang.Object,java.util.function.Supplier)">
</a><a id="requireNonNullElseGet(T,java.util.function.Supplier)">
<ul class="blockList">
<li class="blockList">
<h4>requireNonNullElseGet</h4>
<pre class="methodSignature">public static&nbsp;&lt;T&gt;&nbsp;T&nbsp;requireNonNullElseGet&#8203;(T&nbsp;obj,
                                          <a href="function/Supplier.html" title="interface in java.util.function">Supplier</a>&lt;? extends T&gt;&nbsp;supplier)</pre>
<div class="block">Returns the first argument if it is non-<code>null</code> and otherwise
 returns the non-<code>null</code> value of <code>supplier.get()</code>.</div>
<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>T</code> - the type of the first argument and return type</dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>obj</code> - an object</dd>
<dd><code>supplier</code> - of a non-<code>null</code> object to return if the first argument
                 is <code>null</code></dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the first argument if it is non-<code>null</code> and otherwise
         the value from <code>supplier.get()</code> if it is non-<code>null</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if both <code>obj</code> is null and
        either the <code>supplier</code> is <code>null</code> or
        the <code>supplier.get()</code> value is <code>null</code></dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<a id="requireNonNull(java.lang.Object,java.util.function.Supplier)">
</a><a id="requireNonNull(T,java.util.function.Supplier)">
<ul class="blockList">
<li class="blockList">
<h4>requireNonNull</h4>
<pre class="methodSignature">public static&nbsp;&lt;T&gt;&nbsp;T&nbsp;requireNonNull&#8203;(T&nbsp;obj,
                                   <a href="function/Supplier.html" title="interface in java.util.function">Supplier</a>&lt;<a href="../lang/String.html" title="class in java.lang">String</a>&gt;&nbsp;messageSupplier)</pre>
<div class="block">Checks that the specified object reference is not <code>null</code> and
 throws a customized <a href="../lang/NullPointerException.html" title="class in java.lang"><code>NullPointerException</code></a> if it is.
 <p>Unlike the method <a href="#requireNonNull(T,java.lang.String)"><code>requireNonNull(Object, String)</code></a>,
 this method allows creation of the message to be deferred until
 after the null check is made. While this may confer a
 performance advantage in the non-null case, when deciding to
 call this method care should be taken that the costs of
 creating the message supplier are less than the cost of just
 creating the string message directly.</div>
<dt><span class="paramLabel">Type Parameters:</span></dt>
<dd><code>T</code> - the type of the reference</dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>obj</code> - the object reference to check for nullity</dd>
<dd><code>messageSupplier</code> - supplier of the detail message to be
 used in the event that a <code>NullPointerException</code> is thrown</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>obj</code> if not <code>null</code></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/NullPointerException.html" title="class in java.lang">NullPointerException</a></code> - if <code>obj</code> is <code>null</code></dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>1.8</dd>
<a id="checkIndex(int,int)">
<ul class="blockList">
<li class="blockList">
<h4>checkIndex</h4>
<pre class="methodSignature">public static&nbsp;int&nbsp;checkIndex&#8203;(int&nbsp;index,
                             int&nbsp;length)</pre>
<div class="block">Checks if the <code>index</code> is within the bounds of the range from
 <code>0</code> (inclusive) to <code>length</code> (exclusive).
 <p>The <code>index</code> is defined to be out of bounds if any of the
 following inequalities is true:
  <li><code>index &lt; 0</code></li>
  <li><code>index &gt;= length</code></li>
  <li><code>length &lt; 0</code>, which is implied from the former inequalities</li>
 </ul></div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>index</code> - the index</dd>
<dd><code>length</code> - the upper-bound (exclusive) of the range</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>index</code> if it is within bounds of the range</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IndexOutOfBoundsException.html" title="class in java.lang">IndexOutOfBoundsException</a></code> - if the <code>index</code> is out of bounds</dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<a id="checkFromToIndex(int,int,int)">
<ul class="blockList">
<li class="blockList">
<h4>checkFromToIndex</h4>
<pre class="methodSignature">public static&nbsp;int&nbsp;checkFromToIndex&#8203;(int&nbsp;fromIndex,
                                   int&nbsp;toIndex,
                                   int&nbsp;length)</pre>
<div class="block">Checks if the sub-range from <code>fromIndex</code> (inclusive) to
 <code>toIndex</code> (exclusive) is within the bounds of range from <code>0</code>
 (inclusive) to <code>length</code> (exclusive).
 <p>The sub-range is defined to be out of bounds if any of the following
 inequalities is true:
  <li><code>fromIndex &lt; 0</code></li>
  <li><code>fromIndex &gt; toIndex</code></li>
  <li><code>toIndex &gt; length</code></li>
  <li><code>length &lt; 0</code>, which is implied from the former inequalities</li>
 </ul></div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>fromIndex</code> - the lower-bound (inclusive) of the sub-range</dd>
<dd><code>toIndex</code> - the upper-bound (exclusive) of the sub-range</dd>
<dd><code>length</code> - the upper-bound (exclusive) the range</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>fromIndex</code> if the sub-range within bounds of the range</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IndexOutOfBoundsException.html" title="class in java.lang">IndexOutOfBoundsException</a></code> - if the sub-range is out of bounds</dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
<a id="checkFromIndexSize(int,int,int)">
<ul class="blockListLast">
<li class="blockList">
<h4>checkFromIndexSize</h4>
<pre class="methodSignature">public static&nbsp;int&nbsp;checkFromIndexSize&#8203;(int&nbsp;fromIndex,
                                     int&nbsp;size,
                                     int&nbsp;length)</pre>
<div class="block">Checks if the sub-range from <code>fromIndex</code> (inclusive) to
 <code>fromIndex + size</code> (exclusive) is within the bounds of range from
 <code>0</code> (inclusive) to <code>length</code> (exclusive).
 <p>The sub-range is defined to be out of bounds if any of the following
 inequalities is true:
  <li><code>fromIndex &lt; 0</code></li>
  <li><code>size &lt; 0</code></li>
  <li><code>fromIndex + size &gt; length</code>, taking into account integer overflow</li>
  <li><code>length &lt; 0</code>, which is implied from the former inequalities</li>
 </ul></div>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>fromIndex</code> - the lower-bound (inclusive) of the sub-interval</dd>
<dd><code>size</code> - the size of the sub-range</dd>
<dd><code>length</code> - the upper-bound (exclusive) of the range</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><code>fromIndex</code> if the sub-range within bounds of the range</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../lang/IndexOutOfBoundsException.html" title="class in java.lang">IndexOutOfBoundsException</a></code> - if the sub-range is out of bounds</dd>
<dt><span class="simpleTagLabel">Since:</span></dt>
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