code: @Nonnull
    public static XPathExpression createNewXPathExpression (@Nonnull final XPath aXPath,
                                                            @Nonnull @Nonempty final String sXPath)
    {
      ValueEnforcer.notNull (aXPath, "XPath");
      ValueEnforcer.notNull (sXPath, "XPathExpression");
  
      try
      {
        return aXPath.compile (sXPath);
      }
      catch (final XPathExpressionException ex)
      {
        throw new IllegalArgumentException ("Failed to compile XPath expression '" + sXPath + "'", ex);
      }
    }
docs: Create a new XPath expression for evaluation.
  
  @param aXPath
  The pre-created XPath object. May not be <code>null</code>.
  @param sXPath
  The main XPath string to be evaluated
  @return The {@link XPathExpression} object to be used.
  @throws IllegalArgumentException
  if the XPath cannot be compiled