provide sufficient information to re-create an expression. Two different expressions can have
 exactly the same expression string but different function mappings. Serialization should be used to save and restore
 the state of an <code>Expression</code>.
 </p></div>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../el/Expression.html#getExpressionString()">getExpressionString</a></code>&nbsp;in class&nbsp;<code><a href="../../../../el/Expression.html" title=