diff --git a/pom.xml b/pom.xml
index d639c6c26c..825a97fbbe 100644
--- a/pom.xml
+++ b/pom.xml
@@ -188,7 +188,7 @@
 		<dependency>
 			<groupId>mysql</groupId>
 			<artifactId>mysql-connector-java</artifactId>
-			<version>5.1.12</version>
+			<version>5.1.16</version>
 			<scope>test</scope>
 		</dependency>
 		<dependency>
diff --git a/src/main/java/com/alibaba/druid/pool/DruidAbstractDataSource.java b/src/main/java/com/alibaba/druid/pool/DruidAbstractDataSource.java
index a59f2539e7..8c8d042afd 100644
--- a/src/main/java/com/alibaba/druid/pool/DruidAbstractDataSource.java
+++ b/src/main/java/com/alibaba/druid/pool/DruidAbstractDataSource.java
@@ -138,7 +138,7 @@ public abstract class DruidAbstractDataSource implements DruidAbstractDataSource
 
     protected long                 timeBetweenConnectErrorMillis             = DEFAULT_TIME_BETWEEN_CONNECT_ERROR_MILLIS;
 
-    private ValidConnectionChecker validConnectionChecker                    = null;
+    protected ValidConnectionChecker validConnectionChecker                    = null;
 
     public ValidConnectionChecker getValidConnectionChecker() {
         return validConnectionChecker;
diff --git a/src/main/java/com/alibaba/druid/pool/DruidDataSource.java b/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
index 56c8917304..f96548ec37 100644
--- a/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
+++ b/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
@@ -33,6 +33,9 @@ import javax.naming.Referenceable;
 import javax.naming.StringRefAddr;
 
 import com.alibaba.druid.filter.Filter;
+import com.alibaba.druid.pool.vendor.MSSQLValidConnectionChecker;
+import com.alibaba.druid.pool.vendor.MySQLValidConnectionChecker;
+import com.alibaba.druid.pool.vendor.OracleValidConnectionChecker;
 import com.alibaba.druid.proxy.jdbc.DataSourceProxyConfig;
 import com.alibaba.druid.util.JdbcUtils;
 
@@ -74,8 +77,6 @@ public class DruidDataSource extends DruidAbstractDataSource implements DruidDat
     private final CountDownLatch                                                 initedLatch                 = new CountDownLatch(
                                                                                                                                   2);
 
-   
-
     public DruidDataSource(){
     }
 
@@ -129,6 +130,14 @@ public class DruidDataSource extends DruidAbstractDataSource implements DruidDat
 
             this.dbType = JdbcUtils.getDbType(jdbcUrl, driverClass.getClass().getName());
 
+            if ("mysql".equals(dbType)) {
+                this.validConnectionChecker = new MySQLValidConnectionChecker();
+            } else if ("oracle".equals(dbType)) {
+                this.validConnectionChecker = new OracleValidConnectionChecker();
+            } else if ("sqlserver".equals(dbType)) {
+                this.validConnectionChecker = new MSSQLValidConnectionChecker();
+            }
+
             for (Filter filter : filters) {
                 filter.init(this);
             }