package autoChirp.webController;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;

import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.SessionAttributes;
import org.springframework.web.servlet.ModelAndView;

import autoChirp.DBConnector;
import autoChirp.tweetCreation.Tweet;
import autoChirp.tweetCreation.TweetGroup;

@Controller
public class TweetController {

@RequestMapping(value = "/dashboard")
public ModelAndView dashboard(HttpSession session) {
        if (session.getAttribute("account") == null) return new ModelAndView("redirect:/account");

        ModelAndView mv = new ModelAndView("dashboard");
        return mv;
}

}

package autoChirp.webController;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;

import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.SessionAttributes;
import org.springframework.web.servlet.ModelAndView;

import autoChirp.DBConnector;
import autoChirp.tweetCreation.Tweet;
import autoChirp.tweetCreation.TweetGroup;

@Controller
public class DashboardController {

@RequestMapping(value = "/dashboard")
public ModelAndView dashboard(HttpSession session) {
        if (session.getAttribute("account") == null) return new ModelAndView("redirect:/account");

        ModelAndView mv = new ModelAndView("dashboard");
        return mv;
}

}

Rename controller, because.