Java ServletContext

Question

I have a JSP web site, not Spring MVC, and it has a config file web.xml.

There are a couple of settings within the web.xml file that I\'d like to get.

However, I

Answer 1

Using a javax.servlet.ServletContextListener implementation, that allows a singleton-like access to context:

package test.dummy;
import javax.servlet.ServletContextListener;
import javax.servlet.ServletContextEvent;

public  class ContextConfiguration implements ServletContextListener {

  private static ContextConfiguration _instance;

  private ServletContext context = null;

  //This method is invoked when the Web Application
  //is ready to service requests
  public void contextInitialized(ServletContextEvent event) {
    this.context = event.getServletContext();

    //initialize the static reference _instance
     _instance=this;
  }

  /*This method is invoked when the Web Application has been removed 
  and is no longer able to accept requests
  */
  public void contextDestroyed(ServletContextEvent event) {
    this.context = null;

  }

  /* Provide a method to get the context values */
  public String getContextParameter(String key) {
     return this.context.getInitParameter(key);
  }

  //now, provide an static method to allow access from anywere on the code:
  public static ContextConfiguration getInstance() {
     return _instance;
  }
}

Set it up at web.xml:

    
     test.dummy.ContextConfiguration
    
  


 

And use it from anywhere at the code:

ContextConfiguration config=ContextConfiguration.getInstance();
String paramValue=config.getContextParameter("parameterKey");