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copied!<blockquote> <h3><a href="http://docs.oracle.com/javase/specs/jls/se5.0/html/names.html#6.4.5" rel="nofollow noreferrer">JLS 6.4.5 The Members of an Array Type</a></h3> <p>The members of an array type are all of the following:</p> <ul> <li>The <code>public final field length</code>, which contains the number of components of the array (length may be positive or zero).</li> <li>The <code>public</code> method <code>clone</code>, which overrides the method of the same name in class <code>Object</code> and throws no checked exceptions. The return type of the clone method of an array type <code>T[]</code> is <code>T[]</code>.</li> <li>All the members inherited from class <code>Object</code>; the only method of <code>Object</code> that is not inherited is its <code>clone</code> method. </li> </ul> </blockquote> <p>Thus:</p> <pre><code>byte[] original = ...; byte[] copy = original.clone(); </code></pre> <p>Note that for array of reference types, <code>clone()</code> is essentially a <em><a href="https://en.wikipedia.org/wiki/Object_copying#Shallow_copy" rel="nofollow noreferrer">shallow copy</a></em>.</p> <p>Also, Java doesn't have multidimensional arrays; it has array of arrays. Thus, a <code>byte[][]</code> is an <code>Object[]</code>, and is also subject to <em>shallow copy</em>.</p> <h3>See also</h3> <ul> <li><a href="http://en.wikipedia.org/wiki/Object_copy" rel="nofollow noreferrer">Wikipedia/Object copy</a></li> <li><a href="https://docs.oracle.com/javase/tutorial/java/nutsandbolts/arrays.html" rel="nofollow noreferrer">Java Nuts and Bolts/Arrays</a></li> </ul> <h3>Related questions</h3> <ul> <li><a href="https://stackoverflow.com/questions/200387/deep-cloning-multidimensional-arrays-in-java"> Deep cloning multidimensional arrays in Java… ? </a></li> <li><a href="https://stackoverflow.com/questions/2589741/how-to-effectively-copy-an-array-in-java">How to effectively copy an array in java ?</a></li> <li><a href="https://stackoverflow.com/questions/419858/how-to-deep-copy-an-irregular-2d-array">How to deep copy an irregular 2D array</a></li> <li><a href="https://stackoverflow.com/questions/1564832/how-do-i-do-a-deep-copy-of-a-2d-array-in-java"> How do I do a deep copy of a 2d array in Java? </a></li> </ul> <hr> <h3>Other options</h3> <p>Note that <code>clone()</code> returns a <em>new</em> array object. If you simply want to copy the values from one array to an already existing array, you can use e.g. <a href="http://download.oracle.com/docs/cd/E17409_01/javase/6/docs/api/java/lang/System.html#arraycopy%28java.lang.Object,%20int,%20java.lang.Object,%20int,%20int%29" rel="nofollow noreferrer"><code>System.arraycopy</code></a>.</p> <p>There's also <a href="http://download.oracle.com/docs/cd/E17409_01/javase/6/docs/api/java/util/Arrays.html#copyOf%28byte%5B%5D,%20int%29" rel="nofollow noreferrer"><code>java.util.Arrays.copyOf</code></a> that allows you to create a copy with a different length (either truncating or padding).</p> <h3>Related questions</h3> <ul> <li><a href="https://stackoverflow.com/questions/1697250/difference-between-various-array-copy-methods"> Difference between various Array copy methods </a></li> </ul>

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