Merge pull request #7276 in CORE/base-third from bugfix/11.0 to feature/x

* commit '97f67e2c7b6a37f08b589db9c7e2b11ea3e939f8':
  REPORT-83447  改下注释
  REPORT-83447  驱动管理mysql自定义连接和druid监控不兼容

fine-druid/src/main/java/com/fr/third/alibaba/druid/util/MySqlUtils.java

@@ -16,6 +16,7 @@
 package com.fr.third.alibaba.druid.util;
 
 import com.fr.third.alibaba.druid.DbType;
+import com.fr.third.alibaba.druid.proxy.jdbc.ConnectionProxy;
 import com.fr.third.alibaba.druid.sql.SQLUtils;
 import com.fr.third.alibaba.druid.sql.ast.statement.SQLCreateTableStatement;
 
@@ -403,8 +404,13 @@ public class MySqlUtils {
     }
 
     public static long getLastPacketReceivedTimeMs(Connection conn) throws SQLException {
-
-        ClassLoader cl = conn.getClass().getClassLoader();
+        // durid监控若开启，Connection 对象是 ConnectionProxy ，且ConnectionProxy和Connection不一定在同一个类加载器下
+        ClassLoader cl;
+        if (conn instanceof ConnectionProxy) {
+            cl = ((ConnectionProxy) conn).getRawObject().getClass().getClassLoader();
+        } else {
+            cl = conn.getClass().getClassLoader();
+        }
         ConnectionClass cc = classLoaderConnectionClassMap.compute(cl, (k, v) -> {
             if (v == null || v.class_connectionImpl.getClassLoader() != cl) {
                 return new ConnectionClass();