struts2 + hibernate + mysql数据库 放在windows XP tomcat服务器上。
该项目运行一段时间 或者隔夜就报错，
而且是访问登录页不报错，一旦点击登录就报错。换句话说就是访问数据库报错。
以本人浅薄的知识初步判断为mysql数据库8小时无连接自动关闭的原因。
但是延长了数据库关闭的时间，依旧如此。
以下为tomcat后台报错：
2012-1-14 8:47:37 org.apache.catalina.core.StandardWrapperValve invoke
: Servlet.service() for servlet default threw exception
java.lang.IllegalStateException
at org.apache.catalina.connector.ResponseFacade.sendError(ResponseFacade.java:407)
at org.apache.struts2.dispatcher.Dispatcher.sendError(Dispatcher.java:707)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:488)
at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:467)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)
以下为前台页面报错：
Struts has detected an unhandled exception:
Messages: Software caused connection abort: socket write error
The last packet successfully received from the server was57161 milliseconds ago.The last packet sent successfully to the server was 57161 milliseconds 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.
FreeMarker template error!
Method public java.lang.String org.hibernate.exception.NestableRuntimeException.getMessage(int) threw an exception when invoked on org.hibernate.exception.JDBCConnectionException: could not execute query
The problematic instruction:
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==> ${msg[0]} [on line 68, column 29 in org/apache/struts2/dispatcher/error.ftl]
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Java backtrace for programmers:
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freemarker.template.TemplateModelException: Method public java.lang.String org.hibernate.exception.NestableRuntimeException.getMessage(int) threw an exception when invoked on org.hibernate.exception.JDBCConnectionException: could not execute query
at freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:130)
at freemarker.ext.beans.SimpleMethodModel.get(SimpleMethodModel.java:138)
at freemarker.core.DynamicKeyName.dealWithNumericalKey(DynamicKeyName.java:111)
at freemarker.core.DynamicKeyName._getAsTemplateModel(DynamicKeyName.java:90)
at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
at freemarker.core.Expression.getStringValue(Expression.java:93)
at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
at freemarker.core.Environment.visit(Environment.java:208)
at freemarker.core.MixedContent.accept(MixedContent.java:92)
at freemarker.core.Environment.visit(Environment.java:208)
at freemarker.core.IfBlock.accept(IfBlock.java:82)
at freemarker.core.Environment.visit(Environment.java:208)
at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:179)