Merge pull request #1880 from Am-phi/fix/JDBC_driver_prints_stack_trace_to_stdout

Fix JDBC driver prints stack trace to stdout

Author: chernser

clickhouse-client/src/main/java/com/clickhouse/client/ClickHouseClient.java

@@ -40,6 +40,8 @@
 import com.clickhouse.data.ClickHouseValue;
 import com.clickhouse.data.ClickHouseValues;
 import com.clickhouse.data.ClickHouseWriter;
+import com.clickhouse.logging.Logger;
+import com.clickhouse.logging.LoggerFactory;
 
 /**
  * A unified interface defines Java client for ClickHouse. A client can only
@@ -56,6 +58,7 @@
  * implementation properly in runtime.
  */
 public interface ClickHouseClient extends AutoCloseable {
+    Logger LOG = LoggerFactory.getLogger(ClickHouseClient.class);
 
     /**
      * Returns a builder for creating a new client.
@@ -959,8 +962,8 @@ default boolean ping(ClickHouseNode server, int timeout) {
                     .get(timeout, TimeUnit.MILLISECONDS)) {
                 return resp != null;
             } catch (Exception e) {
-                // ignore
-                e.printStackTrace();
+                LOG.debug("Failed to connect to the server", e);
+                return false;
             }
         }
 

client-v2/src/main/java/com/clickhouse/client/api/Client.java

@@ -1037,6 +1037,7 @@ public boolean ping(long timeout) {
             try (QueryResponse response = query("SELECT 1 FORMAT TabSeparated").get(timeout, TimeUnit.MILLISECONDS)) {
                 return true;
             } catch (Exception e) {
+                LOG.debug("Failed to connect to the server", e);
                 return false;
             }
         } else {