title: How to Check null for double type of value in java
body: <p>I have A double type of variable. I want to check whether the variable is null or not. I read that double will never become null, They suggested me to change datatype double to Double. If I change double to Double I am Having performance issue.Here I need to check null pointer.</p>
  
  <pre><code>double dbl=ParentBean.getChildBean().getDays();
  </code></pre>
  
  <p>How to check <code>dbl</code> is null or not.
  Thanks in advance.</p>