com.mysql.jdbc.connection.isvalid

先牢骚一句哈:今天这个问题,搞了我大半天(想哭),希望小伙伴们能越过这个坑! 问题描述: 有时我们浏览器会出现这样一个问题,如下图所示: 问题原因: tomcat中JDBC驱动jar包过旧. 我们原始在tomcat的lib目录下的JDBC的驱动jar包的版本如下图所示: 解决方法: 下载较新的JDBC驱动版本:mysql-connector-java-5.1.46-bin.jar,官网下载地址:http://dev.mysql.com/downloads/connector/j/ 注意:不要下载

package com.swift; //这里导入的包是java.sql.Connection而不是com.mysql.jdbc.Connection import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; public class TestJDBC { public static void main(String[] args) { try { Class.forName(

写jsp加载数据驱动以后老是提示Only a type can be imported. com.mysql.jdbc.Connection resolves to a package的错误,然而改成java就无报错 出错的原因:没有成功引入包 解决方法:将mysql-connector-java-5.1.39-bin.jar放到tomcat的bin目录下就可以解决  

1.完成对数据库的表的增删改的操作 2.查询返回单条记录 3.查询返回多行记录 4.可以使用反射机制来封装,查询单条记录 5.反射机制,查询多条记录 package myjdbc; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.HashMap; import java.util.

com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'receiverTel='123131' payment=0,time ='2015-04-10 10:14', trade

com.mysql.jdbc.exceptions.MySQLNonTransientConnectionException: Too many connections at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:921) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2822) at com.mysql.jdbc.MysqlIO.checkErrorPa

最简单的办法是因为你的my.ini中设定的并发连接数太少或者系统繁忙导致连接数被占满解决方式:打开MySQL安装目录打开MY.INI找到max_connections默认是100 .--实例 WINDOWS解决mysql Errno.: 1040错误XXXX info: Can not connect to MySQL server User: rootTime: 2004-5-20 3:00pmScript: /XXXX/XXXX.PHP Error: Too many connections

在运行"maven build"-->"tomcat:run"之后,报如下错误: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

web开发遇到的异常: com.mysql.jdbc.CommunicationsException:The last packet successfully received from the server was58129 seconds ago.Thelast packet sent successfully to the server was 58129 seconds ago, which islonger than the server configured value of 'wa