title: How to check Solr Status with SolrPing
body: <p>I need to check if Solr machine and Solr service are up and running;
  I have a java server who need to know that. I use SolrJ library to communicate with Solr and query it. I use Solr 7.3.0
  I think I can test Solr status with SolrPing class, but I always get this exception.</p>
  
  <pre><code>Server refused connection at: http://localhost:8983/solr
  </code></pre>
  
  <p>this is my solr ping call</p>
  
  <pre><code>SolrClient solrClient = new HttpSolrClient(solrBaseUrl);
  SolrPing solrPing = new SolrPing();
  SolrPingResponse pingResponse = solrPing.process(solrClient);
  int status = pingResponse.getStatus();
  System.out.println(status);
  </code></pre>
  
  <p>What do I miss ? It fails on .process call. solrBaseUrl is correct, and my solr istance is shutted down (so I should expect something like status -1)</p>
  
  <p>Thanks to you all</p>