From 33957a51273ea9d524b0dc57194299657127edf7 Mon Sep 17 00:00:00 2001
From: wenshao <szujobs@hotmail.com>
Date: Wed, 29 Jun 2011 09:47:21 +0000
Subject: [PATCH] =?UTF-8?q?=E4=BB=A3=E7=A0=81=E9=87=8D=E6=9E=84?=
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git-svn-id: http://code.alibabatech.com/svn/druid/trunk@314 b9813039-fb51-4c41-a8b9-e21c2acb5095
---
 .../druid/pool/vendor/MySqlValidConnectionChecker.java    | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

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 62752d3095..eaa7090cb5 100644
--- a/src/main/java/com/alibaba/druid/pool/vendor/MySqlValidConnectionChecker.java
+++ b/src/main/java/com/alibaba/druid/pool/vendor/MySqlValidConnectionChecker.java
@@ -35,18 +35,16 @@ public class MySqlValidConnectionChecker implements ValidConnectionChecker, Seri
     }
 
     public boolean isValidConnection(Connection c) {
+        Connection conn = null;
         try {
-            Connection conn = (Connection) c.unwrap(clazz);
-            if (conn != null) {
-                c = conn;
-            }
+            conn = (Connection) c.unwrap(clazz);
         } catch (SQLException e) {
             LOG.warn("Unexpected error in ping", e);
             return false;
         }
 
         // if there is a ping method then use it, otherwise just use a 'SELECT 1' statement
-        if (driverHasPingMethod) {
+        if (conn != null && driverHasPingMethod) {
             try {
                 ping.invoke(c);
                 return true;