struts-sandbox/mailreader-course/struts2/theme/src/java/AuthenticationInterceptor.java

import com.opensymphony.xwork2.Action;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;
import org.apache.struts.apps.mailreader.dao.User;

import java.util.Map;

public class AuthenticationInterceptor implements Interceptor {

    public void destroy() {
    }

    public void init() {
    }

    public String intercept(ActionInvocation actionInvocation) throws Exception {

        Map session = actionInvocation.getInvocationContext().getSession();

        User user = (User) session.get(MailReaderSupport.USER_KEY);

        boolean isAuthenticated = (null != user) && (null != user.getDatabase());

        if (!isAuthenticated) {
            return Action.LOGIN;
        } else {
            return actionInvocation.invoke();
        }

    }
}