Implement Connection#isValid

jdbc-v2/src/main/java/com/clickhouse/jdbc/ConnectionImpl.java

@@ -15,6 +15,7 @@
 import com.clickhouse.jdbc.internal.ParsedPreparedStatement;
 import com.clickhouse.jdbc.internal.SqlParser;
 import com.clickhouse.jdbc.metadata.DatabaseMetaDataImpl;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -35,6 +36,7 @@
 import java.sql.Savepoint;
 import java.sql.Statement;
 import java.sql.Struct;
+import java.time.Duration;
 import java.util.Arrays;
 import java.util.Calendar;
 import java.util.Collections;
@@ -487,13 +489,15 @@ public SQLXML createSQLXML() throws SQLException {
 
     @Override
     public boolean isValid(int timeout) throws SQLException {
-        checkOpen();
         if (timeout < 0) {
             throw new SQLException("Timeout must be >= 0", ExceptionUtils.SQL_STATE_CLIENT_ERROR);
         }
-
-        //TODO: This is a placeholder implementation
-        return true;
+        if (isClosed()) {
+            return false;
+        }
+        return timeout == 0
+            ? client.ping()
+            : client.ping(Duration.ofSeconds(timeout).toMillis());
     }
 
     @Override

jdbc-v2/src/test/java/com/clickhouse/jdbc/ConnectionTest.java

@@ -13,6 +13,7 @@
 import com.github.tomakehurst.wiremock.client.WireMock;
 import com.github.tomakehurst.wiremock.common.ConsoleNotifier;
 import com.github.tomakehurst.wiremock.core.WireMockConfiguration;
+
 import org.testng.Assert;
 import org.testng.annotations.DataProvider;
 import org.testng.annotations.Test;
@@ -34,7 +35,6 @@
 import static org.testng.Assert.assertThrows;
 import static org.testng.Assert.fail;
 
-
 public class ConnectionTest extends JdbcIntegrationTest {
 
     @Test(groups = { "integration" }, enabled = false)
@@ -569,8 +569,32 @@ public void testConnectionWithValidDatabaseName(String dbName) throws Exception
         connCheck.close();
     }
 
+    @Test(groups = { "integration" })
+    public void closedConnectionIsInvalid() throws Exception {
+        if (isCloud()) {
+            return;
+        }
+        Connection connection = this.getJdbcConnection();
+        Assert.assertTrue(connection.isValid(3));
+        connection.close();
+        Assert.assertFalse(connection.isValid(3));
+    }
+
+    @Test(groups = { "integration" })
+    public void connectionWithWrongCredentialsIsInvalid() throws Exception {
+        if (isCloud()) {
+            return;
+        }
+        Connection connection = this.getJdbcConnection();
+        Assert.assertTrue(connection.isValid(3));
+        Properties properties = new Properties();
+        properties.put("password", "invalid");
+        connection = this.getJdbcConnection(properties);
+        Assert.assertFalse(connection.isValid(3));
+    }
+
     @DataProvider(name = "validDatabaseNames")
-    public Object[][] createValidDatabaseNames() {
+    private static Object[][] createValidDatabaseNames() {
         return new Object[][] {
             { "foo" },
             { "with-dashes" },