关闭Tomcat(7.0)老出现这样的严重提示org.apache.catalina.loader

写一个应用程序上下文监听器，在contextDestroyed方法中加入如下代码：
DriverManager.deregisterDriver(DriverManager.getDriver(url));
如果你不知道url，那就这样：

Enumeration<Driver> drivers = DriverManager.getDrivers();
while (drivers.hasMoreElements()) {
    Driver driver = drivers.nextElement();
    try {
        DriverManager.deregisterDriver(driver);
        Logger.getLogger(
                this.class.getName())
                .log(Level.INFO,
                        String.format("deregistering jdbc driver: %s",
                                driver), driver);
    } catch (SQLException e) {
        Logger.getLogger(
                this.class.getName())
                .log(Level.SEVERE,
                        String.format("Error deregistering driver %s",
                                driver), e);
    }
}