title: Memory leak error in tomcat server even after removed quartz related code
body: <p>I am working on web project based on spring hibernate.I am using c3p0 for connection pooling.Sometimes the server is automatically stopped and showing that </p>
  
  <blockquote>
    <p>"The web application registered JDBC driver but failed to unregister"</p>
  </blockquote>
  
  <p>.And also the following error.</p>
  
  <blockquote>
    <p>"The web application appears to have started
    DefaultQuartzSchelduler_Worker_1 but has failed to stop"
    <a href="https://i.stack.imgur.com/euDjP.png" rel="noreferrer"><img src="https://i.stack.imgur.com/euDjP.png" alt="enter image description here"></a></p>
  </blockquote>
  
  <p>This error is still occurs after i have removed Quartz job related code in my project.I have closed all the stream which causes memory leaks but still I dont know why this is happening.Please help me out regarding this issue  because the project is in live.
  Thanks </p>