解决 java.lang.IllegalStateException

1、案例

信息: Illegal access: this web application instance has been stopped already.

 Could not load oracle.net.mesg.Message.  
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

2、原因

网络适配器无法创建连接

根本原因：无法连接到数据库

3、解决

查看网络是数据库连接是否通畅，解决。