<p>Is there any performance reason to declare method parameters final in Java?</p>

<p>As in:</p>

<pre><code>public void foo(int bar) { ... }
</code></pre>

<p>Versus:</p>

<pre><code>public void foo(final int bar) { ... }
</code></pre>

<p>Assuming that <code>bar</code> is only read and never modified in <code>foo()</code>.</p>

Compilers that operate after class loading, such as JIT compilers, can take advantage of final methods. Consequently, methods declared final could have some performance benefit.
http://www.javaperformancetuning.com/tips/final.shtml
Oh and another good resource
http://mindprod.com/jgloss/final.html