SolrUtils help with recurring tasks when working with Solr like escaping and sanitizing user input.
use InterNations\Component\Solr\Expression\Expression\Util;
// Quote a string to be used in a query
Util::quote('(term)'); // "\(term\)"
// Escape a string but not quote it
Util::escape('(term)'); // \(term\)
// Sanitize a string to be used safely in a query
Util::sanitize('term'); // term