tomcat重启警告：Abandoned connection cleanup thread 服务器宕机解决方案

每次出现这个报错都会导致tomcat应用服务器停机

报错信息:

The web application [HelloWeb] appears to have started a thread named [Abandoned connection cleanup thread] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
         java.lang.Object.wait(Native Method)
         java.lang.ref.ReferenceQueue.remove(Unknown Source)
         com.mysql.jdbc.AbandonedConnectionCleanupThread.run(AbandonedConnectionCleanupThread.java:43)

加了下面的java代码后就再也没有停过了。

package cn.listener;

import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Enumeration;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;

import com.mysql.jdbc.AbandonedConnectionCleanupThread;


@WebListener
public class ContextFinalizer implements ServletContextListener {

    public void contextInitialized(ServletContextEvent sce) {
    }

    public void contextDestroyed(ServletContextEvent sce) {
        Enumeration<Driver> drivers = DriverManager.getDrivers();
        Driver d = null;
        while (drivers.hasMoreElements()) {
            try {
                d = drivers.nextElement();
                DriverManager.deregisterDriver(d);
                System.out.println(String.format("ContextFinalizer:Driver %s deregistered", d));
            } catch (SQLException ex) {
                System.out.println(String.format("ContextFinalizer:Error deregistering driver %s", d) + ":" + ex);
            }
        }
        try {
            AbandonedConnectionCleanupThread.shutdown();
        } catch (InterruptedException e) {
            System.out.println("ContextFinalizer:SEVERE problem cleaning up: " + e.getMessage());
            e.printStackTrace();
        }
    }
}

@WebListener，这个注解相当于在web.xml配置如下内容

  <listener>
    <listener-class>cn.listener.ContextFinalizer</listener-class>
  </listener>