string connectStr = "Server=localhost;port=3306;Database=xxx;User ID=root;Password=xxx;"; MySqlConnection conn = new MySqlConnection(connectStr);//仍还没有建立连接 try { conn.Open();//建立连接 //string sql = "select * from users";//sql语句 //MySqlCommand cmd = new MySqlCommand(sql, conn);//建立命令 } catch(MySqlException ex) { } 异常信息： Authentication to host 'localhost' for user 'root' using method 'caching_sha2_password' failed with message: Access denied for user 'root'@'localhost' (using password: YES) 请问一下，mysql8.0.15不支持net4.0吗 我尝试修改验证方式： alter user ‘root’@'localhost' identified with mysql_native_password by '密码'; 但是也没用 详细异常信息 在 MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.AuthenticationFailed(Exception ex) 在 MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.ReadPacket() 在 MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.ContinueAuthentication(Byte[] data) 在 MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.Authenticate(Boolean reset) 在 MySql.Data.MySqlClient.NativeDriver.Open() 在 MySql.Data.MySqlClient.Driver.Open() 在 MySql.Data.MySqlClient.Driver.Create(MySqlConnectionStringBuilder settings) 在 MySql.Data.MySqlClient.MySqlPool.CreateNewPooledConnection() 在 MySql.Data.MySqlClient.MySqlPool.GetPooledConnection() 在 MySql.Data.MySqlClient.MySqlPool.TryToGetDriver() 在 MySql.Data.MySqlClient.MySqlPool.GetConnection() 在 MySql.Data.MySqlClient.MySqlConnection.Open() 在 ConsoleAppMySql.Program.Connection() 位置 G:\数据库例子\ConsoleAppMySql\ConsoleAppMySql\Program.cs:行号 29

语句和报错如下 这是表内容 求大神解答

sc delete mysql [SC] DeleteService 成功 net start mysql 服务名无效。 请键入 NET HELPMSG 2185 以获得更多的帮助。

 这是什么问题 应该输入 mysqld --skip-grant-tables这个DOS命令窗口不可动了啊

十一月 25, 2018 10:20:42 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh 信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@47089e5f: startup date [Sun Nov 25 22:20:42 CST 2018]; root of context hierarchy 十一月 25, 2018 10:20:42 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions 信息: Loading XML bean definitions from class path resource [spring-dao.xml] org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Client does not support authentication protocol requested by server; consider upgrading MySQL client) at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1549) at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1388) at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044) at day06.DataSourceTest.testConnection(DataSourceTest.java:24) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:89) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:41) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:541) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:763) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:463) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:209) Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Client does not support authentication protocol requested by server; consider upgrading MySQL client at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.Util.getInstance(Util.java:381) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3558) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3490) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:919) at com.mysql.jdbc.MysqlIO.secureAuth411(MysqlIO.java:3996) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1284) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2137) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:776) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:352) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:284) at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38) at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582) at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556) at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545) ... 26 more 十一月 25, 2018 10:20:43 下午 org.springframework.context.support.ClassPathXmlApplicationContext doClose 信息: Closing org.springframework.context.support.ClassPathXmlApplicationContext@47089e5f: startup date [Sun Nov 25 22:20:42 CST 2018]; root of context hierarchy 今天我想测试一下eclipse能不能连到mysql上 可是他报错 提示我让我升级数据库 我的数据库是8.0.12的 应该不低才对啊 import org.apache.commons.dbcp.BasicDataSource; import org.junit.Test; import org.springframework.context.support.AbstractApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class DataSourceTest { @Test public void testConnection() { AbstractApplicationContext ac=new ClassPathXmlApplicationContext("spring-dao.xml"); BasicDataSource ds=ac.getBean("dataSource",BasicDataSource.class); Connection conn=null; try { conn=ds.getConnection(); System.out.println(conn); } catch (Exception e) { e.printStackTrace(); }finally { if(conn!=null) { try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } } } ac.close(); } } 这是代码，希望大哥帮下

<div class="post-text" itemprop="text"> 如何设置MySQL Datetime列的默认值? 在SQL Server中是 <code>getdate()</code>. MySQL的等效功能是什么？ 如果这是一个原因的话，那么我来使用MySQL5.x尝试一下。</p> </div> <p>转载于:https://stackoverflow.com/questions/168736/how-do-you-set-a-default-value-for-a-mysql-datetime-column</p>

我们之前的MySQL驱动是6.0.6的，现在升级到8.0.11后，别的问题没有，就在插入大量数据时出现了问题，我们使用的是load datalocal infile插入的； 以下是出现问题的代码： ``` try { if(inputStream == null){ logger.info("InputStream is null ,No data is imported"); return 0; } conn = jdbcTemplate.getDataSource().getConnection(); statement = conn.prepareStatement(sql); if (statement.isWrapperFor(Statement.class)) { com.mysql.cj.jdbc.ServerPreparedStatement mysqlStatement = statement.unwrap(com.mysql.cj.jdbc.ServerPreparedStatement.class); mysqlStatement.setLocalInfileInputStream(inputStream); result = mysqlStatement.executeUpdate(); } return result; } catch (Exception e) { logger.info("批量插入eda数据异常，原因: " + e.getMessage()); } ``` 这个是出现的报错信息： ``` 批量插入eda数据异常，原因: Unable to unwrap to class com.mysql.cj.jdbc.ServerPreparedStatement ``` 查了好久都没有找到解决办法，各位大神帮忙啊，感激不尽

django连接mysql提示 django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module. Did you install mysqlclient? 也就是说要我pip install mysqlclient 可我安装mysql的时候自带MySQL Connector Python 8.0 for Python 3.7 C:\Program Files\MySQL\MySQL Connector Python 8.0 for Python 3.7 也就是说我只要告诉django连接mysql用这个目录里的文件就好了... 可我怎么才能让django知道这件事...

 用的是MySQL官网的示例，只把数据库用户名密码改成了自己的。用户名密码没问题，可在CMD登陆MySQL。但是Eclipse一直报错，url, user, password分开写也不行。  求大佬解答

各位好，请教有谁熟悉centos下安装mysql的，遇到一个问题一直无法解决： centos7最小安装版本下rpm方式安装mysql，但是一直报缺少perl依赖，但是已经安装了。 1、安装了ActivePerl-5.20在/opt/ActivePerl-5.20目录下 2、已经配置path（/etc/profile) 3、已经用in命令将perl从/opt/ActivePerl-5.20/bin/perl链接到/usr/bin目录 4、在命令行下，任意目录执行perl -version，正常获取到perl的版本 但是安装mysql，还是缺少/usr/bin/perl？请问怎么解决，以下截图是相关截图，请问谁知道怎么解决，谢谢

在环境变量以及my.ini文件都正好以后 再Cmd输入mysqld --initialize --consol之后出现了以下神秘代码。。这是为什么？ E:\SQL\mysql-8.0.15-winx64>mysqld --initialize --console mysqld: Can't create directory 'C:\Program Files\MySQL\Data\' (OS errno 2 - No such file or directory) 2019-03-26T16:13:27.803255Z 0 [System] [MY-013169] [Server] E:\SQL\mysql-8.0.15-winx64\bin\mysqld.exe (mysqld 8.0.15) initializing of server in progress as process 10504 2019-03-26T16:13:27.803525Z 0 [ERROR] [MY-010338] [Server] Can't find error-message file 'C:\Program Files\MySQL\share\errmsg.sys'. Check error-message file location and 'lc-messages-dir' configuration directive. 2019-03-26T16:13:27.805036Z 0 [Warning] [MY-013242] [Server] --character-set-server: 'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous. 2019-03-26T16:13:27.809940Z 0 [ERROR] [MY-013236] [Server] Newly created data directory C:\Program Files\MySQL\Data\ is unusable. You can safely remove it. 2019-03-26T16:13:27.876969Z 0 [ERROR] [MY-010119] [Server] Aborting 2019-03-26T16:13:27.877380Z 0 [System] [MY-010910] [Server] E:\SQL\mysql-8.0.15-winx64\bin\mysqld.exe: Shutdown complete (mysqld 8.0.15) MySQL Community Server - GPL. ``` 图在此(https://img-ask.csdn.net/upload/201903/27/1553617467_17340.png) ``` 以下是我配置的图片

ecplise2019-03连接数据库mysql8.0出错，我的ecplise连接SQL是好的 import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; public class a1 { public static void main(String []args) { Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; // The newInstance() call is a work around for some // broken Java implementations try { Class.forName("com.mysql.jdbc.Driver"); System.out.println("加载成功"); conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/shop?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC","root","qing980104"); System.out.println("连接成功"); } } catch (SQLException ex) { // handle any errors System.out.println("连接失败"); } } } 结果显示 Exception in thread "main" java.lang.ClassNotFoundException: com.microsoft.sqlserver.jdbc.SQLServerDriver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:315) at experiment1.a1.main(a1.java:7) 我把代码换成运行成功的SQL连接代码，然后改了下 import java.sql.*; public class a1 { public static void main(String[] args) throws SQLException, ClassNotFoundException { // TODO Auto-generated method stub Class.forName("com.mysql.cj.jdbc.Driver"); Connection conn= DriverManager.getConnection(jdbc:mysql://127.0.0.1:3306/shop?serverTimezone=GMT%2B8","root","qing980104"); Statement stm=conn.createStatement(); ResultSet re=stm.executeQuery("select * from book"); while(re.next()) { System.out.println("书名："+re.getString(1)+"书号："+re.getString(2)+"价格："+re.getString(3)); } re.close(); stm.close(); conn.close(); } } 结果显示 Exception in thread "main" java.sql.SQLException: Access denied for user ''@'localhost' (using password: NO) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:835) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:455) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199) at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:677) at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:251) at mysql.connector.java@8.0.15/com.mysql.cj.jdbc.admin.TimezoneDump.main(TimezoneDump.java:70) 我以前写的java课设中连接数据库也是显示上面（using password: NO）这个结果 网上有说是MySQL8.0用了强密码的缘故，我重下装了改成旧方式，但还是不行，我又重装了n次，结果现在只能是旧方式，无法改成强密码方式。而且程序还是不行。求大佬解答

java.lang.ClassNotFoundException: com.mysql.cj.jdbc.driver at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Unknown Source) at util.try1.main(try1.java:29) 数据库连接失败 代码 package util; import java.beans.Statement; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import com.mysql.cj.jdbc.Driver; public class try1 { private static String DBUrl="jdbc:mysql://localhost:3306/bishe?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf-8&useSSL=false"; private static String DBUser="root"; private static String DBPwd="xsj123..0"; public static Connection conn=null; public static ResultSet rs=null; public static PreparedStatement pst=null; public static void main(String[] args) { // TODO Auto-generated method stub try { String Driver = "com.mysql.cj.jdbc.driver"; Class.forName(Driver); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); System.out.println("数据库连接失败"); } try { DriverManager.getConnection(DBUrl, DBUser, DBPwd); } catch (SQLException e1) { // TODO Auto-generated catch block e1.printStackTrace(); System.out.println("数据库连接失败1"); }

最近在学习mvc，写了一个简单的demo，其中连接MySQL数据库的Java类如下： 但是老报错： package myjava; import java.sql.*; public class myjavabean { Connection conn; Statement stmt; ResultSet rs1; ResultSet rs2; public myjavabean(){ try{ Class.forName("com.mysql.jdbc.Driver"); conn=DriverManager.getConnection("jdbc:mysql://localhost:3308/mvc_user?useUnicode=true&characterEncoding=UTF-8","root","123456"); stmt=conn.createStatement(); } catch(Exception e) { e.printStackTrace(); } } public String login(String name, String password){ String message="abc"; try{ String sql1="select count(0) from user_info where user_name='"+name+"'"; rs1=stmt.executeQuery(sql1); if(rs1.next()){ int userCount=rs1.getInt(1); if(0==userCount){ message="不存在该用户"; return message; } String sql2="select count(0) from user_info where user_name='"+name+"'and password='"+password+"'"; rs2=stmt.executeQuery(sql2); if(rs2.next()){ int trueUserCount=rs2.getInt(1); if(0==trueUserCount){ message="密码错误"; return message; } message="成功!"; } } }catch(Exception e) { e.printStackTrace(); }finally{ try{ if(rs1!=null){ rs1.close(); System.out.println("rs1 is not null"); } if(rs1==null){ System.out.println("rs1 is null"); } if(rs2!=null){ rs2.close(); } if(stmt!=null){ stmt.close(); } if(conn!=null){ conn.close(); } }catch(SQLException e){ System.out.println(e.toString()); } } return message; } } eclipse控制台报如下错误： com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.net.SocketException MESSAGE: java.net.ConnectException: Connection refused: connect STACKTRACE: java.net.SocketException: java.net.ConnectException: Connection refused: connect at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:156) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:276) at com.mysql.jdbc.Connection.createNewIO(Connection.java:2592) at com.mysql.jdbc.Connection.<init>(Connection.java:1509) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266) at java.sql.DriverManager.getConnection(Unknown Source) at java.sql.DriverManager.getConnection(Unknown Source) at myjava.myjavabean.<init>(myjavabean.java:10) at myjava.myservlet.doGet(myservlet.java:42) at myjava.myservlet.doPost(myservlet.java:62) at javax.servlet.http.HttpServlet.service(HttpServlet.java:646) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:315) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) ** END NESTED EXCEPTION ** Last packet sent to the server was 9 ms ago. at com.mysql.jdbc.Connection.createNewIO(Connection.java:2658) at com.mysql.jdbc.Connection.<init>(Connection.java:1509) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266) at java.sql.DriverManager.getConnection(Unknown Source) at java.sql.DriverManager.getConnection(Unknown Source) at myjava.myjavabean.<init>(myjavabean.java:10) at myjava.myservlet.doGet(myservlet.java:42) at myjava.myservlet.doPost(myservlet.java:62) at javax.servlet.http.HttpServlet.service(HttpServlet.java:646) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:315) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) java.lang.NullPointerException at myjava.myjavabean.login(myjavabean.java:22) at myjava.myservlet.doGet(myservlet.java:43) at myjava.myservlet.doPost(myservlet.java:62) at javax.servlet.http.HttpServlet.service(HttpServlet.java:646) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:315) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source)

我点了update project后，项目就报错了，是怎么回事？   

按照右击项目名，build path，添加jar包，测试数据库连接类的时候依然抛出异常，请问怎么解决？正确的方法是什么？ 

java.sql.SQLException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:76) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:835) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:455) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:136) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:369) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:198) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:467) [HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:541) [HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:115) [HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:112) [HikariCP-3.2.0.jar:na] at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection(DataSourceUtils.java:157) [spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:115) [spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:78) [spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:82) [mybatis-spring-2.0.0.jar:2.0.0] at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:68) [mybatis-spring-2.0.0.jar:2.0.0] at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:336) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:85) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83) [mybatis-3.5.0.jar:3.5.0] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_152] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_152] at org.apache.ibatis.plugin.Invocation.proceed(Invocation.java:49) [mybatis-3.5.0.jar:3.5.0] at com.github.pagehelper.SqlUtil._processPage(SqlUtil.java:401) [pagehelper-4.1.4.jar:na] at com.github.pagehelper.SqlUtil.processPage(SqlUtil.java:374) [pagehelper-4.1.4.jar:na] at com.github.pagehelper.PageHelper.intercept(PageHelper.java:254) [pagehelper-4.1.4.jar:na] at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61) [mybatis-3.5.0.jar:3.5.0] at com.sun.proxy.$Proxy79.query(Unknown Source) [na:na] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) [mybatis-3.5.0.jar:3.5.0] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_152] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_152] at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433) [mybatis-spring-2.0.0.jar:2.0.0] at com.sun.proxy.$Proxy65.selectList(Unknown Source) [na:na] at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:230) [mybatis-spring-2.0.0.jar:2.0.0] at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:144) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:77) [mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:58) [mybatis-3.5.0.jar:3.5.0] at com.sun.proxy.$Proxy84.queryActivitybyType(Unknown Source) [na:na] at com.elephants.biz.ActivityBiz.selectActivitybyType(ActivityBiz.java:29) [classes/:na] at com.elephants.biz.ActivityBiz$$FastClassBySpringCGLIB$$143d4670.invoke(<generated>) [classes/:na] at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) [spring-core-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:749) [spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) [spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294) ~[spring-tx-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) [spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688) ~[spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at com.elephants.biz.ActivityBiz$$EnhancerBySpringCGLIB$$d9954339.selectActivitybyType(<generated>) ~[classes/:na] at com.elephants.action.ActivityAction.queryActivityByType(ActivityAction.java:32) ~[classes/:na] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_152] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_152] at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:189) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:897) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:634) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:200) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:834) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[na:1.8.0_152] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[na:1.8.0_152] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at java.lang.Thread.run(Thread.java:748) ~[na:1.8.0_152] Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_152] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_152] at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:85) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.util.TimeUtil.getCanonicalTimezone(TimeUtil.java:132) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.protocol.a.NativeProtocol.configureTimezone(NativeProtocol.java:2241) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.protocol.a.NativeProtocol.initServerSession(NativeProtocol.java:2265) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:1319) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:966) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:825) ~[mysql-connector-java-8.0.15.jar:8.0.15] ... 110 common frames omitted 2019-03-11 10:20:35.248 ERROR 5184 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. ### The error may exist in file [D:\Twolittleelephants\website\target\classes\mapping\ActivityMapping.xml] ### The error may involve com.elephants.dao.IActivityDao.queryActivitybyType ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.] with root cause com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_152] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_152] at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:85) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.util.TimeUtil.getCanonicalTimezone(TimeUtil.java:132) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.protocol.a.NativeProtocol.configureTimezone(NativeProtocol.java:2241) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.protocol.a.NativeProtocol.initServerSession(NativeProtocol.java:2265) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:1319) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:966) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:825) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:455) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199) ~[mysql-connector-java-8.0.15.jar:8.0.15] at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:136) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:369) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:198) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:467) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:541) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:115) ~[HikariCP-3.2.0.jar:na] at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:112) ~[HikariCP-3.2.0.jar:na] at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection(DataSourceUtils.java:157) ~[spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:115) ~[spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:78) ~[spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:82) ~[mybatis-spring-2.0.0.jar:2.0.0] at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:68) ~[mybatis-spring-2.0.0.jar:2.0.0] at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:336) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:85) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83) ~[mybatis-3.5.0.jar:3.5.0] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_152] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_152] at org.apache.ibatis.plugin.Invocation.proceed(Invocation.java:49) ~[mybatis-3.5.0.jar:3.5.0] at com.github.pagehelper.SqlUtil._processPage(SqlUtil.java:401) ~[pagehelper-4.1.4.jar:na] at com.github.pagehelper.SqlUtil.processPage(SqlUtil.java:374) ~[pagehelper-4.1.4.jar:na] at com.github.pagehelper.PageHelper.intercept(PageHelper.java:254) ~[pagehelper-4.1.4.jar:na] at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61) ~[mybatis-3.5.0.jar:3.5.0] at com.sun.proxy.$Proxy79.query(Unknown Source) ~[na:na] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) ~[mybatis-3.5.0.jar:3.5.0] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_152] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_152] at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433) ~[mybatis-spring-2.0.0.jar:2.0.0] at com.sun.proxy.$Proxy65.selectList(Unknown Source) ~[na:na] at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:230) ~[mybatis-spring-2.0.0.jar:2.0.0] at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:144) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:77) ~[mybatis-3.5.0.jar:3.5.0] at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:58) ~[mybatis-3.5.0.jar:3.5.0] at com.sun.proxy.$Proxy84.queryActivitybyType(Unknown Source) ~[na:na] at com.elephants.biz.ActivityBiz.selectActivitybyType(ActivityBiz.java:29) ~[classes/:na] at com.elephants.biz.ActivityBiz$$FastClassBySpringCGLIB$$143d4670.invoke(<generated>) ~[classes/:na] at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:749) ~[spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294) ~[spring-tx-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688) ~[spring-aop-5.1.5.RELEASE.jar:5.1.5.RELEASE] at com.elephants.biz.ActivityBiz$$EnhancerBySpringCGLIB$$d9954339.selectActivitybyType(<generated>) ~[classes/:na] at com.elephants.action.ActivityAction.queryActivityByType(ActivityAction.java:32) ~[classes/:na] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_152] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_152] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_152] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_152] at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:189) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:897) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:634) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882) ~[spring-webmvc-5.1.5.RELEASE.jar:5.1.5.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:200) ~[tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:834) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415) [tomcat-embed-core-9.0.16.jar:9.0.16] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.16.jar:9.0.16] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_152] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_152] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.16.jar:9.0.16] at java.lang.Thread.run(Thread.java:748) [na:1.8.0_152]

在mysql-8.0.18 中导入外部数据表格时，出现了错误ERROR 29 (HY000):(OS errno 2 - No such file or directory) 具体如下图： mysql> load data infile 'C:/工作文档/学习文件/t1.csv' -> into table t1 -> fields terminated by ',' -> ignore 1 lines; ERROR 29 (HY000): File 'C:\工作文档\学习文件\t1.csv' not found (OS errno 2 - No such file or directory) 查看了不少攻略，发现都不管用，请问该如何解决？ ``` ```

这是怎么回事呢？用的本地服务器wampserver老是出现这种问题，mysql确实已启动，数据库、表都建了，就是查不到任何数据！图片说明](https://img-ask.csdn.net/upload/201504/10/1428666719_317504.jpg)

今年，我也32了 ，为了不给大家误导，咨询了猎头、圈内好友，以及年过35岁的几位老程序员……舍了老脸去揭人家伤疤……希望能给大家以帮助，记得帮我点赞哦。 目录： 你以为的人生 一次又一次的伤害 猎头界的真相 如何应对互联网行业的「中年危机」 一、你以为的人生 刚入行时，拿着傲人的工资，想着好好干，以为我们的人生是这样的： 等真到了那一天，你会发现，你的人生很可能是这样的： ...

程序员在一个周末的时间，得了重病，差点当场去世，还好及时挽救回来了。

互联网公司工作，很难避免不和黑客们打交道，我呆过的两家互联网公司，几乎每月每天每分钟都有黑客在公司网站上扫描。有的是寻找 Sql 注入的缺口，有的是寻找线上服务器可能存在的漏洞，大部分都...

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原博客再更新，可能就没了，之后将持续更新本篇博客。

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私下里，有不少读者问我：“二哥，如何才能写出一份专业的技术简历呢？我总感觉自己写的简历太烂了，所以投了无数份，都石沉大海了。”说实话，我自己好多年没有写过简历了，但我认识的一个同行，他在阿里，给我说了一些他当年写简历的方法论，我感觉太牛逼了，实在是忍不住，就分享了出来，希望能够帮助到你。 01、简历的本质 作为简历的撰写者，你必须要搞清楚一点，简历的本质是什么，它就是为了来销售你的价值主张的。往深...

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二哥，有个事想询问下您的意见，您觉得应届生值得去外包吗？公司虽然挺大的，中xx，但待遇感觉挺低，马上要报到，挺纠结的。

当HR压你价，说你只值7K时，你可以流畅地回答，记住，是流畅，不能犹豫。 礼貌地说：“7K是吗？了解了。嗯~其实我对贵司的面试官印象很好。只不过，现在我的手头上已经有一份11K的offer。来面试，主要也是自己对贵司挺有兴趣的，所以过来看看……”（未完） 这段话主要是陪HR互诈的同时，从公司兴趣，公司职员印象上，都给予对方正面的肯定，既能提升HR的好感度，又能让谈判气氛融洽，为后面的发挥留足空间。...

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最近面试了一个31岁8年经验的程序猿，让我有点感慨，大龄程序猿该何去何从。

说实话，自己的算法，我一个不会，太难了吧

已经连续五年参加大厂校招、社招的技术面试工作，简历看的不下于万份 这篇文章会用实例告诉你，什么是差的程序员简历！ 疫情快要结束了，各个公司也都开始春招了，作为即将红遍大江南北的新晋UP主，那当然要为小伙伴们做点事（手动狗头）。 就在公众号里公开征简历，义务帮大家看，并一一点评。《启舰：春招在即，义务帮大家看看简历吧》 一石激起千层浪，三天收到两百多封简历。 花光了两个星期的所有空闲时...

正确选择比瞎努力更重要！

正确选择比瞎努力更重要！

文章目录1. 无状态登录1.1 什么是有状态1.2 什么是无状态1.3 如何实现无状态1.4 各自优缺点2. 登录交互2.1 前后端分离的数据交互2.2 登录成功2.3 登录失败3. 未认证处理方案4. 注销登录 这是本系列的第四篇，有小伙伴找不到之前文章，松哥给大家列一个索引出来： 挖一个大坑，Spring Security 开搞！ 松哥手把手带你入门 Spring Security，别再问密...

轻松等回家通知

大厂竟然要考我SSO，卧槽。

他可能没想到，我当场手写出来了

来看几个问题想不想月薪超过5万？想不想进入公司架构组？想不想成为项目组的负责人？想不想成为spring的高手，超越99%的对手？那么本文内容是你必须要掌握的。本文主要详解bean的生命...

不怕告诉你，我自从喜欢上了这12个UP主，哔哩哔哩成为了我手机上最耗电的软件，几乎每天都会看，可是吧，看的越多，我就越觉得自己是个废柴，唉，老天不公啊，不信你看看…… 间接性踌躇满志，持续性混吃等死，都是因为你们……但是，自己的学习力在慢慢变强，这是不容忽视的，推荐给你们！ 都说B站是个宝，可是有人不会挖啊，没事，今天咱挖好的送你一箩筐，首先啊，我在B站上最喜欢看这个家伙的视频了，为啥 ，咱撇...

某站后端代码被“开源”，同时刷遍全网的，还有代码里的那些神注释。 我们这才知道，原来程序员个个都是段子手；这么多年来，我们也走过了他们的无数套路… 首先，产品经理，是永远永远吐槽不完的！网友的评论也非常扎心，说看这些代码就像在阅读程序员的日记，每一页都写满了对产品经理的恨。 然后，也要发出直击灵魂的质问：你是尊贵的付费大会员吗？ 这不禁让人想起之前某音乐app的穷逼Vip，果然，穷逼在哪里都是...