How to pass Arrays to Methods in Java?

You can pass arrays to a method just like normal variables. When we pass an array to a method as an argument, actually the address of the array in the memory is passed (reference). Therefore, any changes to this array in the method will affect the array.

Suppose we have two methods min() and max() which accepts an array and these methods calculates the minimum and maximum values of the given array respectively:

Example

<span class="kwd">import</span><span class="pln"> java</span><span class="pun">.</span><span class="pln">util</span><span class="pun">.</span><span class="typ">Scanner</span><span class="pun">;</span><span class="pln">

</span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">ArraysToMethod</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
   </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">int</span><span class="pln"> max</span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> </span><span class="pun">[]</span><span class="pln"> array</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
      </span><span class="kwd">int</span><span class="pln"> max </span><span class="pun">=</span><span class="pln"> </span><span class="lit">0</span><span class="pun">;</span><span class="pln">

      </span><span class="kwd">for</span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> i</span><span class="pun">=</span><span class="lit">0</span><span class="pun">;</span><span class="pln"> i</span><span class="pun"><</span><span class="pln">array</span><span class="pun">.</span><span class="pln">length</span><span class="pun">;</span><span class="pln"> i</span><span class="pun">++</span><span class="pln"> </span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
         </span><span class="kwd">if</span><span class="pun">(</span><span class="pln">array</span><span class="pun">[</span><span class="pln">i</span><span class="pun">]></span><span class="pln">max</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
            max </span><span class="pun">=</span><span class="pln"> array</span><span class="pun">[</span><span class="pln">i</span><span class="pun">];</span><span class="pln">
         </span><span class="pun">}</span><span class="pln">
      </span><span class="pun">}</span><span class="pln">
      </span><span class="kwd">return</span><span class="pln"> max</span><span class="pun">;</span><span class="pln">
   </span><span class="pun">}</span><span class="pln">

   </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">int</span><span class="pln"> min</span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> </span><span class="pun">[]</span><span class="pln"> array</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
      </span><span class="kwd">int</span><span class="pln"> min </span><span class="pun">=</span><span class="pln"> array</span><span class="pun">[</span><span class="lit">0</span><span class="pun">];</span><span class="pln">
   
      </span><span class="kwd">for</span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> i </span><span class="pun">=</span><span class="pln"> </span><span class="lit">0</span><span class="pun">;</span><span class="pln"> i</span><span class="pun"><</span><span class="pln">array</span><span class="pun">.</span><span class="pln">length</span><span class="pun">;</span><span class="pln"> i</span><span class="pun">++</span><span class="pln"> </span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
         </span><span class="kwd">if</span><span class="pun">(</span><span class="pln">array</span><span class="pun">[</span><span class="pln">i</span><span class="pun">]<</span><span class="pln">min</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
            min </span><span class="pun">=</span><span class="pln"> array</span><span class="pun">[</span><span class="pln">i</span><span class="pun">];</span><span class="pln">
         </span><span class="pun">}</span><span class="pln">
      </span><span class="pun">}</span><span class="pln">
      </span><span class="kwd">return</span><span class="pln"> min</span><span class="pun">;</span><span class="pln">
   </span><span class="pun">}</span><span class="pln">

   </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">void</span><span class="pln"> main</span><span class="pun">(</span><span class="typ">String</span><span class="pln"> args</span><span class="pun">[])</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
      </span><span class="typ">Scanner</span><span class="pln"> sc </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">Scanner</span><span class="pun">(</span><span class="typ">System</span><span class="pun">.</span><span class="kwd">in</span><span class="pun">);</span><span class="pln">
      </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="str">"Enter the size of the array that is to be created::"</span><span class="pun">);</span><span class="pln">
      </span><span class="kwd">int</span><span class="pln"> size </span><span class="pun">=</span><span class="pln"> sc</span><span class="pun">.</span><span class="pln">nextInt</span><span class="pun">();</span><span class="pln">
      </span><span class="kwd">int</span><span class="pun">[]</span><span class="pln"> myArray </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="kwd">int</span><span class="pun">[</span><span class="pln">size</span><span class="pun">];</span><span class="pln">
      </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="str">"Enter the elements of the array ::"</span><span class="pun">);</span><span class="pln">

      </span><span class="kwd">for</span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> i</span><span class="pun">=</span><span class="lit">0</span><span class="pun">;</span><span class="pln"> i</span><span class="pun"><</span><span class="pln">size</span><span class="pun">;</span><span class="pln"> i</span><span class="pun">++)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
         myArray</span><span class="pun">[</span><span class="pln">i</span><span class="pun">]</span><span class="pln"> </span><span class="pun">=</span><span class="pln"> sc</span><span class="pun">.</span><span class="pln">nextInt</span><span class="pun">();</span><span class="pln">
      </span><span class="pun">}</span><span class="pln">
      </span><span class="typ">ArraysToMethod</span><span class="pln"> m </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">ArraysToMethod</span><span class="pun">();</span><span class="pln">
      </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="str">"Maximum value in the array is::"</span><span class="pun">+</span><span class="pln">m</span><span class="pun">.</span><span class="pln">max</span><span class="pun">(</span><span class="pln">myArray</span><span class="pun">));</span><span class="pln">
      </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="str">"Minimum value in the array is::"</span><span class="pun">+</span><span class="pln">m</span><span class="pun">.</span><span class="pln">min</span><span class="pun">(</span><span class="pln">myArray</span><span class="pun">));</span><span class="pln">
   </span><span class="pun">}</span><span class="pln">
</span><span class="pun">}</span>

Output

Enter the size of the array that is to be created ::
5
Enter the elements of the array ::
45
12
48
53
55
Maximum value in the array is ::55
Minimum value in the array is ::12