我究竟做错了什么？ 尝试通过ServletContextListener在web.xml中使用context-param

Question

I am trying to use init-param in my web-app, and use it together with ServletContextListener. This should later be picked up my the servlet and displayed to the user. I have done everything I can, but I am getting an error. Something is wrong and I can't see it.

My web.xml

<web-app>
<context-param>
<param-name>name</param-name>
<param-value>Abdi</param-value>
</context-param>
</web-app>

My class:

@WebListener
 public class Developer implements ServletContextListener{


@Override
public void contextDestroyed(ServletContextEvent e) {


    System.out.println("Destroyed!");



}

@Override
public void contextInitialized(ServletContextEvent e) {
    ServletContext cntxt = e.getServletContext();

    String name = e.getServletContext().getInitParameter(name); 

    DevInfo student = new DevInfo(name);

    cntxt.setAttribute("student", student); 

}



  }

Other class:

public class DevInfo {

private String name;


public DevInfo (String name) {
    this.name = name;

}

public String getName() {
    return name;
}

}

Servlet:

   DevInfo stu = (DevInfo)getServletContext().getAttribute("student");

    System.out.println("Developers name is: " + stu.getName());

My error is in the contextInitialized method. "The local variable name may not have been initialized" at e.getServletContext().getInitParameter(name);

Answer 1

The actual way to get the context-param 's param-value is to pass the param-name on the getInitParameter method:

String name = e.getServletContext().getInitParameter("name");

You forgot to put name in quotes.