diff --git a/src/main/java/com/alibaba/druid/pool/DruidDataSource.java b/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
index 9cc8e1c7bb..e04405a53c 100644
--- a/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
+++ b/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
@@ -274,7 +274,10 @@ public class DruidDataSource extends DruidAbstractDataSource implements DruidDat
             if (isTestOnBorrow()) {
                 boolean validate = testConnectionInternal(poolalbeConnection.getConnection());
                 if (!validate) {
-                    LOG.debug("skip not validate connection.");
+                    if (LOG.isDebugEnabled()) {
+                        LOG.debug("skip not validate connection.");
+                    }
+                    
                     Connection realConnection = poolalbeConnection.getConnection();
                     JdbcUtils.close(realConnection);
                     continue;
diff --git a/src/main/java/com/alibaba/druid/pool/ValidConnectionChecker.java b/src/main/java/com/alibaba/druid/pool/ValidConnectionChecker.java
index 30fcc87b88..4f41aee33b 100644
--- a/src/main/java/com/alibaba/druid/pool/ValidConnectionChecker.java
+++ b/src/main/java/com/alibaba/druid/pool/ValidConnectionChecker.java
@@ -3,5 +3,5 @@ package com.alibaba.druid.pool;
 import java.sql.Connection;
 
 public interface ValidConnectionChecker {
-    boolean isValidConnection(Connection c, String query, int validationQueryTimeout);
+    boolean isValidConnection(Connection c, String query, int validationQueryTimeout) ;
 }
diff --git a/src/main/java/com/alibaba/druid/pool/vendor/MSSQLValidConnectionChecker.java b/src/main/java/com/alibaba/druid/pool/vendor/MSSQLValidConnectionChecker.java
index 08f4ba9ed3..a2aa16787c 100644
--- a/src/main/java/com/alibaba/druid/pool/vendor/MSSQLValidConnectionChecker.java
+++ b/src/main/java/com/alibaba/druid/pool/vendor/MSSQLValidConnectionChecker.java
@@ -21,6 +21,19 @@ public class MSSQLValidConnectionChecker implements ValidConnectionChecker, Seri
     private static final Log    LOG              = LogFactory.getLog(MSSQLValidConnectionChecker.class);
 
     public boolean isValidConnection(final Connection c, String valiateQuery, int validationQueryTimeout) {
+        try {
+            if (c.isClosed()) {
+                return false;
+            }
+        } catch (SQLException ex) {
+         // skip 
+            return false;
+        }
+
+        if (valiateQuery == null) {
+            return true;
+        }
+
         Statement stmt = null;
 
         try {
diff --git a/src/main/java/com/alibaba/druid/pool/vendor/MySqlValidConnectionChecker.java b/src/main/java/com/alibaba/druid/pool/vendor/MySqlValidConnectionChecker.java
index c1cad974f1..5af4f81f45 100644
--- a/src/main/java/com/alibaba/druid/pool/vendor/MySqlValidConnectionChecker.java
+++ b/src/main/java/com/alibaba/druid/pool/vendor/MySqlValidConnectionChecker.java
@@ -36,19 +36,32 @@ public class MySqlValidConnectionChecker implements ValidConnectionChecker, Seri
         }
     }
 
-    public boolean isValidConnection(Connection c, String valiateQuery, int validationQueryTimeout) {
+    public boolean isValidConnection(Connection conn, String valiateQuery, int validationQueryTimeout) {
+        try {
+            if (conn.isClosed()) {
+                return false;
+            }
+        } catch (SQLException ex) {
+         // skip 
+            return false;
+        }
+        
+        if (valiateQuery == null) {
+            return true;
+        }
+        
         if (driverHasPingMethod) {
-            if (c instanceof PoolableConnection) {
-                c = ((PoolableConnection) c).getConnection();
+            if (conn instanceof PoolableConnection) {
+                conn = ((PoolableConnection) conn).getConnection();
             }
 
-            if (c instanceof ConnectionProxy) {
-                c = ((ConnectionProxy) c).getConnectionRaw();
+            if (conn instanceof ConnectionProxy) {
+                conn = ((ConnectionProxy) conn).getConnectionRaw();
             }
 
-            if (clazz.isAssignableFrom(c.getClass())) {
+            if (clazz.isAssignableFrom(conn.getClass())) {
                 try {
-                    ping.invoke(c);
+                    ping.invoke(conn);
                     return true;
                 } catch (Exception e) {
                     LOG.warn("Unexpected error in ping", e);
@@ -60,7 +73,7 @@ public class MySqlValidConnectionChecker implements ValidConnectionChecker, Seri
         Statement stmt = null;
         ResultSet rs = null;
         try {
-            stmt = c.createStatement();
+            stmt = conn.createStatement();
             stmt.setQueryTimeout(validationQueryTimeout);
             rs = stmt.executeQuery(valiateQuery);
             return true;
diff --git a/src/main/java/com/alibaba/druid/pool/vendor/OracleValidConnectionChecker.java b/src/main/java/com/alibaba/druid/pool/vendor/OracleValidConnectionChecker.java
index 926d896eaa..4b06066705 100644
--- a/src/main/java/com/alibaba/druid/pool/vendor/OracleValidConnectionChecker.java
+++ b/src/main/java/com/alibaba/druid/pool/vendor/OracleValidConnectionChecker.java
@@ -55,19 +55,32 @@ public class OracleValidConnectionChecker implements ValidConnectionChecker, Ser
         }
     }
 
-    public boolean isValidConnection(Connection c, String valiateQuery, int validationQueryTimeout) {
+    public boolean isValidConnection(Connection conn, String valiateQuery, int validationQueryTimeout) {
         try {
-            if (c instanceof PoolableConnection) {
-                c = ((PoolableConnection) c).getConnection();
+            if (conn.isClosed()) {
+                return false;
+            }
+        } catch (SQLException ex) {
+            // skip 
+            return false;
+        }
+        
+        if (valiateQuery == null) {
+            return true;
+        }
+        
+        try {
+            if (conn instanceof PoolableConnection) {
+                conn = ((PoolableConnection) conn).getConnection();
             }
 
-            if (c instanceof ConnectionProxy) {
-                c = ((ConnectionProxy) c).getConnectionRaw();
+            if (conn instanceof ConnectionProxy) {
+                conn = ((ConnectionProxy) conn).getConnectionRaw();
             }
 
             // unwrap
-            if (clazz.isAssignableFrom(c.getClass())) {
-                Integer status = (Integer) ping.invoke(c, params);
+            if (clazz.isAssignableFrom(conn.getClass())) {
+                Integer status = (Integer) ping.invoke(conn, params);
 
                 // Error
                 if (status.intValue() < 0) {
@@ -80,7 +93,7 @@ public class OracleValidConnectionChecker implements ValidConnectionChecker, Ser
             Statement stmt = null;
             ResultSet rs = null;
             try {
-                stmt = c.createStatement();
+                stmt = conn.createStatement();
                 rs = stmt.executeQuery(valiateQuery);
                 return true;
             } catch (SQLException e) {
diff --git a/src/test/java/com/alibaba/druid/pool/benckmark/Case3.java b/src/test/java/com/alibaba/druid/pool/benckmark/Case3.java
index 18079bd1f5..a494806859 100644
--- a/src/test/java/com/alibaba/druid/pool/benckmark/Case3.java
+++ b/src/test/java/com/alibaba/druid/pool/benckmark/Case3.java
@@ -47,15 +47,15 @@ public class Case3 extends TestCase {
         driverClass = "com.alibaba.druid.mock.MockDriver";
 //        connectionProperties = "connectSleep=3;executeSleep=1";
 
-        jdbcUrl = "jdbc:mysql://10.20.153.104:3306/druid2";
-        user = "root";
-        password = "root";
-        driverClass = "com.mysql.jdbc.Driver";
+//        jdbcUrl = "jdbc:mysql://10.20.153.104:3306/druid2";
+//        user = "root";
+//        password = "root";
+//        driverClass = "com.mysql.jdbc.Driver";
     }
 
     public void test_perf() throws Exception {
         for (int i = 0; i < 5; ++i) {
-            druid();
+//            druid();
             dbcp();
             // boneCP();
         }