code: public String cleanAllXPackIndices() throws ElasticSearchException{
  
  			StringBuilder ret = new StringBuilder();
  			for(String monitor:monitorIndices) {
  				try {
  					ret.append(this.client.executeHttp(java.net.URLEncoder.encode(monitor, "UTF-8") + "?pretty", HTTP_DELETE)).append("\n");
  				}
  				catch (Exception e){
  					ret.append(e.getMessage()).append("\n");
  				}
  			}
  			return ret.toString();
  
  		}
docs: 删除所有监控索引
  .security,.monitoring*,.watches,.triggered_watches,.watcher-history*,.ml*
  @return