Generating war package> maven build-> - 1. By run as. No advance clean-up target folder, resulting in extra files into the war package. After the deployment of Tomcat throw an exception.
2. Sometimes the project changing for the better, in the version of Tomcat 7 is always run error. Start a new version 8 of Tomcat, is operating normally. So, when the project deployment is always not up and running, the next to consider the operating environment is not a problem, we need to re-take the next environment.