如何从servlet获取EJB项目中客户端的远程IP地址？

Question

I've created an Enterprise Application project with an EJB project and one web project and it runs fine. Now I would like to get the IP address of the remote client in the EJB project for some logic in my application. I tried to create a context class in the web part as the following:

Context.java

public class Context {
  private static ThreadLocal<Context> instance = new ThreadLocal<Context>();
  private HttpServletRequest request;

  private Context(HttpServletRequest request) {
    this.request = request;
  }

  public static Context getCurrentInstance() {
    return instance.get();
  }

  public static Context newInstance(HttpServletRequest request) {
    Context context = new Context(request);
    instance.set(context);
    return context;
  }

  public HttpServletRequest getRequest() {
    return request;
  }
}

And from class in EJB I tried to call the context class like:

public String setIPAddress() {

    HttpServletRequest request = Context.getCurrentInstance().getRequest();
    String remoteIPAddress = request.getRemoteAddr();

    return remoteIPAddress;
}

My problem is I can't call context.java from EJB class and if I include the classe context in the EJB part I get the NullPointerException. I'v tried also to include the web project in EJB projcet properties and I get the error "Can't add cyclic references". I'm using Netbeans. How can I get the remote IP address in this case?

Answer 1

It is not advisable to do so, but if you need it can use this:

import javax.ejb.Stateless;
import javax.faces.context.FacesContext;
import javax.servlet.http.HttpServletRequest;

@Stateless
public class MyServiceBean {

    public void initialize() {

        final HttpServletRequest request = (HttpServletRequest) FacesContext.getCurrentInstance().getExternalContext().getRequest();
        System.out.println("IP:" + request.getRemoteAddr());

        // load data
    }

}

Answer 2

Having web code ( ServletContext etc) in EJB layer is not a good idea, that makes your business logic tightly coupled to the presentation layer.

A better solution will be to pass the IP address from the presentation logic, rather than, making the EJB later do the work.