Help regarding getParameter-How to use servlet concept in Struts2 Action

[ishan grover]

Hi! all, I Have a problem regarding getparameter. How to access values of textfield through request.getParameter
Please consider the code of jsp as below :

<form action="autocomplete" method="get" name="autofillform"> <table> <tr> <td><s:textfield id="complete-field" onkeyup="doCompletion();" label="City Name"/></td> </tr> <tr> . . .

Javascript code:
function doCompletion() { completeField = document.getElementById("complete-field"); var url = "autocomplete.action?action=complete&id=" + escape(completeField.value); req = initRequest(); req.open("GET", url, true); req.onreadystatechange = callback; req.send(null); } function initRequest() { if (window.XMLHttpRequest) { if (navigator.userAgent.indexOf('MSIE') != -1) { isIE = true; } return new XMLHttpRequest(); } else if (window.ActiveXObject) { isIE = true; return new ActiveXObject("Microsoft.XMLHTTP"); } } . . .

Java Code:
package action; import java.io.IOException; import java.util.HashMap; import java.util.Iterator; import FormBean.*; import com.opensymphony.xwork2.ActionSupport; import db.DAOCity; import javax.servlet.*; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class CityAction extends ActionSupport{ private DAOCity dao = new DAOCity(); private HashMap cities = dao.getCity(); private ServletContext context; public void init(ServletConfig config) throws ServletException { this.context = config.getServletContext(); } private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { System.out.println("IN do get:"); String action = request.getParameter("action"); String targetId = request.getParameter("id"); System.out.println("Action and Id:" + action+" & "+targetId);//Here i m not getting value in console . . .
I am new in Struts2 and don't know how to use servlet concept in Action class.however, I am able to call Action class but not able to retrieve values through getParameter.
Please Help me regarding this.Thanks in Advance

[Mohana Rao Sv]

Try to small example first with struts2. Where is execute method in ActionClass? Why are you calling doGet method here? How to get the request object in Struts2?

[ishan grover]

Mohana Rao Sv wrote:Try to small example first with struts2. Where is execute method in ActionClass? Why are you calling doGet method here? How to get the request object in Struts2?

Actually i want to retrieve list of cities on the basis of dynamic value of textbox.I am trying to implement through ajax. The execute function id down below in action class. I have replaced doget method with execute method as follows
CityAction.java

package action;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import FormBean.*;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import db.DAOCity;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts2.ServletActionContext;

public class CityAction extends ActionSupport{
	private DAOCity dao=new DAOCity();
	@SuppressWarnings("rawtypes")
	private HashMap cities = dao.getCity();
	//ActionContext context = ActionContext.getContext();
	//private ServletContext context;
	HttpServletResponse response;
	ActionContext context = ActionContext.getContext();
	final HttpServletRequest request = (HttpServletRequest) ActionContext.getContext().get(ServletActionContext.HTTP_REQUEST);
	private static final long serialVersionUID = 1L;
        public String execute() throws IOException, ServletException
	{

    String action = request.getParameter("action");
    String targetId = request.getParameter("id");
    System.out.println("ACtion and Id:" + action+" & "+targetId);
    dao.DBCity(targetId);
    StringBuffer sb = new StringBuffer();
    if (targetId != null) {
        targetId = targetId.trim().toLowerCase();
    } else {
    	 ((ServletRequest) context).getRequestDispatcher("/error.jsp").forward(request, response);
    }

    boolean namesAdded = false;
    if (action.equals("complete")) {

        // check if user sent empty string
        if (!targetId.equals("")) {

            Iterator it = cities.keySet().iterator();

            while (it.hasNext()) {
                String id = (String) it.next();
                BeanCity beancity = (BeanCity) cities.get(id);

                if (beancity.getCityname().toLowerCase().startsWith(targetId)) {

                    sb.append("<cities>");
                    sb.append("<id>" + beancity.getId() + "</id>");
                    sb.append("<cityName>" + beancity.getCityname() + "</cityName>");
                    sb.append("</cities>");
                    namesAdded = true;
                }
            }
        }

        if (namesAdded) {
            response.setContentType("text/xml");
            response.setHeader("Cache-Control", "no-cache");
            response.getWriter().write("<cities>" + sb.toString() + "</cities>");
        } else {
            //nothing to show
            response.setStatus(HttpServletResponse.SC_NO_CONTENT);
        }
    }
    if (action.equals("lookup")) {
 
        if ((targetId != null) && cities.containsKey(targetId.trim())) {
            request.setAttribute("cities", cities.get(targetId));
            ((ServletRequest) context).getRequestDispatcher("/demo.jsp").forward(request, response);
        }
    }

		
	return "success";	
	}
}

Now I am getting values from:

 String action = request.getParameter("action");
    String targetId = request.getParameter("id");

The DAO class is as follows where i am fetching cities:
DAOcity.java

package db;
import FormBean.*;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.HashMap;

public class DAOCity {
Integer i=1;
	 HashMap city = new HashMap();
     
	 public HashMap getCity() {
		return city;
	}
     public void setCity(HashMap city) {
		this.city = city;
	}
     public void DBCity(String keyname) {
		try
		{System.out.println("Citykey"+ keyname);
			String key=keyname;
		System.out.println("Cityname :" + key);
			Connection con=ConnectionProviderEEDB.getEEDBConnection();
			PreparedStatement stmtAuto=con.prepareStatement("select * from autocityname where cityname like '%"+key+"%'");
			
			ResultSet rsAuto=stmtAuto.executeQuery();
			System.out.println("\nExecuting query of city database...");
			while(rsAuto.next())
			{
				System.out.println("city database..."+rsAuto.getString(1));
        city.put((int)i, new BeanCity(i.toString(),rsAuto.getString(1)));
        System.out.println("Hash Map"+city.get(i));
        i++;
        }		
		}catch(Exception e)
		{
			System.out.println(e);
		}
		
		System.out.println("Hash Map"+city.get(2));

    }
	}