导致tomcat挂掉的问题

真的不知道该怎样写文章的标题，问题是这样的，前几天开始做权限那块的字段控制，做好后可以跑通，什么都没问题，就是在行控制和列表控制来回点的时候，tomcat就会挂掉，没出现任何的异常。只是重启时报了内存泄露似的异常……郁闷了找了两天，网上搜遍了就是找不到原因。昨晚还是让师兄过来看了下，不到5分钟就找到了问题的所在。哎呀！师兄牛X。

 

我在写代码的时候根本就没有注意hibernate自动生成的dao层的操作数据库的方法，只是调用，根本就没想其他的方法。其实Spring中有两种方法来执行sql或hql操作数据库，分别是getSession()和getHibernateTemplate()

 

使用getSession()必须继承sessionFactory，并且使用getSession()，Spring会把原始的Session给你，你在使用完后必须要自己把session close掉，不然在频繁操作数据库时会占用到所有的链接。也不会对声明式事务进行相应的管理。

 

使用getHibernateTemplate()方法必须继承 HibernateDaoSupport当然包括sessionFactory，它是spring封装好了的，由spring框架帮我们管理session，并且添加了对声明式事务的管理。

 

我就是在dao中使用了getSession()操作数据库并没有手动的去关闭session，而导致tomcat挂掉的。并且这种错误根本就不报任何的异常，如果不对getSession()和getHibernateTemplate()有一定的了解，根本就不会能够想到是这里出的问题，并且这种具体的问题，在网上也没有现成的资料可以参考，真的很感谢师兄啊……

 

以下是tomcat重启扑捉到的，贴上备以后查看

 

2011-3-23 20:32:00 org.apache.coyote.http11.Http11AprProtocol pause信息: Pausing Coyote HTTP/1.1 on http-80862011-3-23 20:32:00 org.apache.coyote.ajp.AjpAprProtocol pause信息: Pausing Coyote AJP/1.3 on ajp-80092011-3-23 20:32:01 org.apache.catalina.core.StandardService stop信息: Stopping service Catalina2011-3-23 20:32:01 org.apache.catalina.core.StandardWrapper unload信息: Waiting for 3 instance(s) to be deallocated2011-3-23 20:32:02 org.apache.catalina.core.StandardWrapper unload信息: Waiting for 3 instance(s) to be deallocated2011-3-23 20:32:03 org.apache.catalina.core.StandardWrapper unload信息: Waiting for 3 instance(s) to be deallocated2011-3-23 20:32:04 org.apache.catalina.core.ApplicationContext log信息: Closing Spring root WebApplicationContext2011-3-23 20:32:04 org.apache.catalina.core.ApplicationContext log信息: Shutting down log4j2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc严重: The web application [/GProject] registered the JBDC driver [oracle.jdbc.driver.OracleDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads严重: The web application [/GProject] appears to have started a thread named [Thread-1] but has failed to stop it. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads严重: The web application [/GProject] is still processing a request that has yet to finish. This is very likely to create a memory leak. You can control the time allowed for requests to finish by using the unloadDelay attribute of the standard Context implementation.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads严重: The web application [/GProject] is still processing a request that has yet to finish. This is very likely to create a memory leak. You can control the time allowed for requests to finish by using the unloadDelay attribute of the standard Context implementation.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads严重: The web application [/GProject] is still processing a request that has yet to finish. This is very likely to create a memory leak. You can control the time allowed for requests to finish by using the unloadDelay attribute of the standard Context implementation.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [null] (value [com.opensymphony.xwork2.inject.ContainerImpl$10@8d0463]) and a value of type [java.lang.Object[]] (value [[Ljava.lang.Object;@1b21b7]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [null] (value [com.opensymphony.xwork2.inject.ContainerImpl$10@8d0463]) and a value of type [java.lang.Object[]] (value [[Ljava.lang.Object;@1897eb0]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@1dc63f6]) and a value of type [org.apache.struts2.dispatcher.Dispatcher] (value [org.apache.struts2.dispatcher.Dispatcher@26c2ff]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@cc24aa]) and a value of type [com.opensymphony.xwork2.ActionContext] (value [com.opensymphony.xwork2.ActionContext@7b1d83]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [null] (value [com.opensymphony.xwork2.inject.ContainerImpl$10@8d0463]) and a value of type [java.lang.Object[]] (value [[Ljava.lang.Object;@cea9a8]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@1dc63f6]) and a value of type [org.apache.struts2.dispatcher.Dispatcher] (value [org.apache.struts2.dispatcher.Dispatcher@26c2ff]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@cc24aa]) and a value of type [com.opensymphony.xwork2.ActionContext] (value [com.opensymphony.xwork2.ActionContext@1e48224]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [null] (value [com.opensymphony.xwork2.inject.ContainerImpl$10@8d0463]) and a value of type [java.lang.Object[]] (value [[Ljava.lang.Object;@11c3ec5]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@1dc63f6]) and a value of type [org.apache.struts2.dispatcher.Dispatcher] (value [org.apache.struts2.dispatcher.Dispatcher@26c2ff]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.2011-3-23 20:32:04 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap严重: The web application [/GProject] created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@cc24aa]) and a value of type [com.opensymphony.xwork2.ActionContext] (value [com.opensymphony.xwork2.ActionContext@15d1e09]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.