title: How to evaluate a math expression given in string form?
body: <p>I'm trying to write a Java routine to evaluate math expressions from <code>String</code> values like:</p>
  <ol>
  <li><code>&quot;5+3&quot;</code></li>
  <li><code>&quot;10-40&quot;</code></li>
  <li><code>&quot;(1+10)*3&quot;</code></li>
  </ol>
  <p>I want to avoid a lot of if-then-else statements.
  How can I do this?</p>