Concatenate null to a string in Java

To concatenate null to a string, use the + operator.

Let’s say the following is our string.

String str = "Demo Text";

We will now see how to effortlessly concatenate null to string.

String strNULL = str + "null";

The following is the final example.

Example

<span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">Demo</span><span class="pln"> </span><span class="pun">{</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="pun">[]</span><span class="pln"> args</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span>
<span class="typ">       String</span><span class="pln"> str </span><span class="pun">=</span><span class="pln"> </span><span class="str">"Demo Text"</span><span class="pun">;</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">"String = "</span><span class="pun">+</span><span class="pln">str</span><span class="pun">);</span>
<span class="typ">       String</span><span class="pln"> strNULL </span><span class="pun">=</span><span class="pln"> str </span><span class="pun">+</span><span class="pln"> </span><span class="str">"null"</span><span class="pun">;</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">"String concatenated with NULL: "</span><span class="pun">+</span><span class="pln">strNULL</span><span class="pun">);</span>
<span class="pun">    }</span>
<span class="pun">}</span>

Output

String = Demo Text
String concatenated with NULL: Demo Textnull