的Tomcat启动失败，因为JDBC驱动程序加载的

Question

这里的tomcat的启动日志的相关部分：

SEVERE: Context [/f360] startup failed due to previous errors 
Apr 8, 2010 6:45:56 PM org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc 
SEVERE: A web application registered the JBDC driver [org.apache.derby.jdbc.ClientDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered. 
Apr 8, 2010 6:45:56 PM org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc 
SEVERE: A web application registered the JBDC driver [oracle.jdbc.OracleDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered. 
Apr 8, 2010 6:45:56 PM org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc 
SEVERE: A web application registered the JBDC driver [com.microsoft.sqlserver.jdbc.SQLServerDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered. 

，它会导致的问题是，它基本上使web应用程序无法正常启动。

任何想法如何解决这个问题？

Answer 1

有关JDBC驱动程序的SEVERE消息是由DBCP问题引起的。请参阅DBCP-332

Answer 2

如果是DBCP问题，请停止tomcat，终止其他进程（如果您有多个tomcat正在运行），请删除tomcat temp目录（也可能是工作目录）并重试。

Answer 3

显然，这是JDBC提供程序堆栈中的一个错误。但无论如何，我以前在码头的一些类似的代码：

public class CleanupContextListener implements ServletContextListener { 
@Override 
public void contextDestroyed(ServletContextEvent servletContextEvent) { 
    Logger logger = Logger.getLogger("CleanupContextListener"); 
    Enumeration<Driver> drivers = DriverManager.getDrivers(); 
    while (drivers.hasMoreElements()) { 
     Driver driver = drivers.nextElement(); 
     ClassLoader driverclassLoader = driver.getClass().getClassLoader(); 
     ClassLoader thisClassLoader = this.getClass().getClassLoader(); 
     if (driverclassLoader != null && thisClassLoader != null && driverclassLoader.equals(thisClassLoader)) { 
      try { 
       logger.warn("Deregistering: " + driver); 
       DriverManager.deregisterDriver(driver); 
      } catch (SQLException e) { 
       e.printStackTrace(); 
      } 
     } 
    } 
} 
@Override 
public void contextInitialized(ServletContextEvent servletContextEvent) {}  

}

Answer 4

有时，特别是使用在Tomcat Spring应用程序时，该错误消息是误导 - 当有在不涉及任何JDBC驱动程序错误除了某些应用程序的BEAN初始化方法（或@PostConstruct）之外，所有这些都失败了。 错误堆栈跟踪是隐藏的，只出现在tomcat/logs/localhost.xxx 文件中。 只需注意这一行为。 这花了我很多时间。

问候， Yosi利