How to declare a constant in java
<p>we always write : </p>

<blockquote>
  <p>public static final int A = 0;  </p>
</blockquote>

<p>Question:  </p>

<p>1) Is <code>static final</code> the only way to declare a <strong>constant</strong> in a class ?<br>
2) if I try this : <code>public final int a = 0;</code> this time, is <strong>A</strong> still a <strong>constant</strong>? or just an <strong>instance field</strong> ?<br>
3) what is an <strong>instance variable</strong> ? what's the difference between an <strong>instance variable</strong> and an <strong>instance field</strong> ?</p>
