How to use wildcard search in apache solr search module?

Question

I am working on apachesolr search module.

I want to implement wildcard search I have used hook_apachesolr_query_prepare() function to modify apachesolr query but it is not working can any one give me solution.
I have implemented code like this.

I have taken reference from here : https://www.drupal.org/project/apachesolr/issues/1539284

function custommodule_apachesolr_query_prepare(DrupalSolrQueryInterface &$query, &$caller) {

  $search = '';
  $keywords = preg_split("/[\s,]+/", $query->getParam('q')); 

  foreach ($keywords as $keyword) {
    $search .= '*' . strtolower($keyword) . '* ';    
  }

  $query->addParam('defType', 'edismax');  
  $query->replaceParam('q', $search);  

}

ENV: Drupal 7.60 | Solr 3.X