非法访问：此Web应用程序实例已被停止。 无法加载org.apache.log4j.spi.NOPLoggerRepository

Question

I am using Netbeans 6.7 with Tomcat 6.0 and jasper reports for generating reports in a web application. I always get this exception when I run my application. can someone please help me out?

The exception is

INFO: Illegal access: this web application instance has been stopped already.  Could not load org.apache.log4j.spi.NOPLoggerRepository.  The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact.
java.lang.IllegalStateException
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1566)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
        at org.apache.log4j.LogManager.getLoggerRepository(LogManager.java:175)
        at org.apache.log4j.LogManager.getLogger(LogManager.java:199)
        at org.apache.log4j.Logger.getLogger(Logger.java:105)
        at org.apache.commons.logging.impl.Log4JLogger.getLogger(Log4JLogger.java:283)
        at org.apache.commons.logging.impl.Log4JLogger.info(Log4JLogger.java:193)
        at org.hibernate.connection.DriverManagerConnectionProvider.close(DriverManagerConnectionProvider.java:147)
        at org.hibernate.connection.DriverManagerConnectionProvider.finalize(DriverManagerConnectionProvider.java:142)
        at java.lang.ref.Finalizer.invokeFinalizeMethod(Native Method)
        at java.lang.ref.Finalizer.runFinalizer(Finalizer.java:83)
        at java.lang.ref.Finalizer.access$100(Finalizer.java:14)
        at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:160)

Answer 1

可能是由于内存问题所致，我收到了此消息以及java.lang.OutOfMemoryError：Java堆空间，将启动参数调整为：-XX：PermSize = 512M -Xms1024m -Xmx4096m解决了该问题。

Answer 2

I found I would get a similar error occasionally while running my JSP web application with Netbeans on Tomcat and always while debugging it. In my case it was "could not load Java.lang.math or Oracle.lnx.lib" . A coworker had me undeploy the web application instances from tomcat and it solved the problem. To undeploy a webapplication instance, go to the Services Tab > Servers and then double click on Apache Tomcat or TomEE and after running the application once since opening netbeans, a Web Applications Folder should appear. If you double click on that, you should see instances of your application appear. You should be able to right click them and then click undeploy (you may have to right click them and hit stop first). Finally, you should stop and then start tomcat before building and running your application.

Hope this helps.