java调用mysql获取不到连接的问题_MySQL

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java调用mysql获取不到连接的问题_MySQL

java调用mysql获取不到连接的问题_MySQL:之前做了一个web项目的时候，好好的网站第二天总是会提示using the Connector/J connection property 'autoReconnect=true' to avoid this problem. 这样的错误com.mysql.jdbc.CommunicationsException: The la

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导读java调用mysql获取不到连接的问题_MySQL:之前做了一个web项目的时候，好好的网站第二天总是会提示using the Connector/J connection property 'autoReconnect=true' to avoid this problem. 这样的错误com.mysql.jdbc.CommunicationsException: The la

之前做了一个web项目的时候，好好的网站第二天总是会提示using the Connector/J connection property 'autoReconnect=true' to avoid this problem. 这样的错误

com.mysql.jdbc.CommunicationsException: The last packet successfully received from the server was58129 seconds ago.The last packet sent successfully to the server was 58129 seconds ago, which is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem.

问题的根本原因是是mysql超时设置的问题。如果连接闲置8小时 (8小时内没有进行数据库操作), mysql就会自动断开连接

第一种解决方案是在 connection url中加参数: autoReconnect=true

jdbc.url=jdbc:mysql://ipaddress:3306/database?autoReconnect=true&autoReconnectForPools=true

第二种如果使用hibernate的时候做如下配置

<property name="connection.autoReconnect">trueproperty>

<property name="connection.autoReconnectForPools">trueproperty>

<property name="connection.is-connection-validation-required">trueproperty>

如果使用了c3p0做如下配置

<property name="hibernate.c3p0.acquire_increment">1property>

<property name="hibernate.c3p0.idle_test_period">0property>

<property name="hibernate.c3p0.timeout">0property>

<property name="hibernate.c3p0.validate">trueproperty>