播放应用程序在空闲状态下死亡，根据新请求重新启动

Question

我正在使用HikariCp，Hibernate和我的java游戏框架应用程序。空闲状态几分钟后，播放应用程序似乎死亡，当它收到新请求时，它会再次启动。有时我还看到Db持久性错误，并显示会话工厂不可用的消息，我认为这是此问题的副作用。为什么应用程序在空闲状态下死亡，我可以如何配置它不这样做吗？

在空闲几分钟内的每个新请求之后，我都会收到以下日志 -

[info] application - Application shutdown...
[info] application - Stopping HikariCP connection pool...
[info] application - Starting HikariCP connection pool...

坚持.xml ：-

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
             version="2.0">
    <persistence-unit name="defaultPersistenceUnit" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <properties>
            <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/> 
            <property name="hibernate.show_sql" value="true"/>
            <property name="hibernate.format_sql" value="true"/>
            <property name="hibernate.use_sql_comments" value="true"/>
            <property name="hibernate.logSql" value="true"/>            
            <property name="hibernate.connection.provider_class" value="com.zaxxer.hikari.hibernate.HikariConnectionProvider"/>
            <property name="hibernate.hikari.dataSourceClassName" value="com.impossibl.postgres.jdbc.PGDataSource"/>
        </properties>
    </persistence-unit>
</persistence>

应用程序：-

# JPA configuration
# ~~~~~
# You can declare as many Ebean servers as you want.
# By convention, the default server is named `default`
jpa.default=defaultPersistenceUnit
# Assets configuration
# ~~~~~
"assets.cache./public/stylesheets/bootstrap.min.css"="max-age=360000"
# Logger
# ~~~~~
# You can also configure logback (http://logback.qos.ch/), by providing a logger.xml file in the conf directory .
# Root logger:
logger=ERROR
# Logger used by the framework:
logger.play=INFO
# Logger provided to your application:
logger.application=DEBUG

谢谢！

Answer 1

数据库连接提供程序在空闲时不执行任何操作以重新连接，您需要向提供程序指示在这种情况下要执行的操作，例如：

    <persistence xmlns="http://java.sun.com/xml/ns/persistence"
                         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                         xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
                         version="2.0">
                <persistence-unit name="defaultPersistenceUnit" transaction-type="RESOURCE_LOCAL">
                    <provider>org.hibernate.ejb.HibernatePersistence</provider>
                    <properties>
                        <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/> 
                        <property name="hibernate.show_sql" value="true"/>
                        <property name="hibernate.format_sql" value="true"/>
                        <property name="hibernate.use_sql_comments" value="true"/>
                        <property name="hibernate.logSql" value="true"/>            
                        <property name="hibernate.connection.provider_class" value="com.zaxxer.hikari.hibernate.HikariConnectionProvider"/>
                        <property name="hibernate.hikari.dataSourceClassName" value="com.impossibl.postgres.jdbc.PGDataSource"

<property name="hibernate.hikari.timeBetweenEvictionRunsMillis="30000" />
        <property name="hibernate.hikari.minEvictableIdleTimeMillis="60000"/>
        <property name="hibernate.hikari.removeAbandonedOnBorrow="true" />    <property name="hibernate.hikari.removeAbandonedOnMaintenance="true" />
    <property name="hibernate.hikari.maxActive="30" />
    <property name="hibernate.hikari.maxIdle="10" />
    <property name="hibernate.hikari.maxWait="10000" />
    <property name="hibernate.hikari.initialSize="5" />
    <property name="hibernate.hikari.validationQuery= "SELECT 1" /> 
    <property name="hibernate.hikari.validationInterval="30000" />
    <property name="hibernate.hikari.removeAbandoned="true" /> 
    <property name="hibernate.hikari.removeAbandonedTimeout="60" /> 
    <property name="hibernate.hikari.logAbandoned="true"/>

                    </properties>
                </persistence-unit>
            </persistence>

查看此链接 https://github.com/brettwooldridge/HikariCP/wiki/Bad-Behavior:-Handling-Database-Down

Answer 2

这背后的原因可能是连接被数据库关闭，因此当应用程序尝试查询这些连接时，sessionFactory 不可用，它将抛出异常。

我

过去遇到过类似的问题，唯一的区别是我使用的是 c3p0 连接池。因此，请尝试为连接提供程序设置connectionTestQuery和idleTimeout属性。

你可以参考这个答案