重新启动MySQL Server后，丢失了与Wildfly的连接

Question

重新启动 MySQL 后，WildFly 连接会丢失。我们使用了 2 个版本的 MySQL，MySQL Ver 14.14 Distrib 5.6.51，用于 Linux (x86_64)，使用 EditLinewrappe 和 MySQL Ver 8.0.28 for Linux on x86_64 (MySQL Community Server - GPL)

我们尝试了 2 个版本的 Wildfly wildfly -10.1.0.Final 和wildfly-19.1.0.Final 我们使用的 JDBC 数据库连接器版本是 - 8.0.19

public static Connection getConnection() throws Exception {
        LOG.debug("returning new connection");
        Class.forName("com.mysql.jdbc.Driver");
        con = DriverManager.getConnection("jdbc:mysql://localhost:3306/xxx?allowPublicKeyRetrieval=true&useSSL=false", "xxxx", "xxxx");
        return con;
    }

如何在重新启动 MySQL 服务器后自动重新连接，最好的方法是什么？

我们收到错误消息

1. 2022-04-08 16:09:36,614 ERROR [xxx.xxx.mysql.MysqlSentSMSDAo] (DefaultQuartzScheduler_Worker-9) No operations allowed after connection closed.: java.sql.SQLNonTransientConnectionException: No operations allowed after connection closed.
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:110)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73)
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:73)
    at com.mysql.cj.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:1659)
    at com.mysql.cj.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:1575)
    at xxx.xxxx.loader.mysql.MysqlSentSMSDAo.selectReplyRecord(MysqlSentSMSDAo.java:85)
    at xxx.xxx.loader.schedular.UpdateReplyReport.execute(UpdateReplyReport.java:109)
    at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
    at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:525)
Caused by: com.mysql.cj.exceptions.ConnectionIsClosedException: No operations allowed after connection closed.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151)
    at com.mysql.cj.NativeSession.checkClosed(NativeSession.java:1171)
    at com.mysql.cj.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:576)
    at com.mysql.cj.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:1590)
    ... 5 more
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure

2. The last packet successfully received from the server was 4,742 milliseconds ago. The last packet sent successfully to the server was 4,744 milliseconds ago.
    at com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174)
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:953)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeQuery(ClientPreparedStatement.java:1003)
    at xxx.xxx.loader.mysql.MysqlSentSMSDAo.getListOfSQLSentSMSEntities(MysqlSentSMSDAo.java:39)
    at xxx.xxx.loader.schedular.UpdateBulkReceipts.execute(UpdateBulkReceipts.java:59)
    at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
    at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:525)
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure

Answer 1

在连接字符串中添加属性autoReconnect=true，使连接自动恢复。如果您使用Wildfly，那么最好在standalone.xml中定义数据源，并在中使用autoReconnect=true标签。

。