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I have problem, this is my code :

file GenericCategories.java

package com.menu.dao.generic;



import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.util.ArrayList;

import java.util.List;



import com.menu.entities.Categories;

import com.menu.entities.Menu;

import com.menu.includes.DBConnect;



public class GenericCategories {

		

	public List SelectAllC() throws Exception {		

		List sac = new ArrayList();

		

		PreparedStatement ps = null;	

		ResultSet rs = null;

		PreparedStatement ps1 = null;	

		ResultSet rs1 = null;

		DBConnect db = new DBConnect();

		Connection con = db.getConnect();

		

		String sql = "SELECT id, category FROM categories";

		

		try {

			ps = con.prepareStatement(sql);

			rs = ps.executeQuery();		

			

			while(rs.next()){	

				Categories c = new Categories();

				

				c.setCategory(rs.getString("category"));

				c.setId(rs.getInt("id"));

				

				String sql2 = "SELECT m.id, m.menu FROM menu m, categories c WHERE c.id = m.cat AND m.cat = ?";

				ps1 = con.prepareStatement(sql2);

				ps1.setInt(1, c.getId());

				rs1 = ps1.executeQuery();				

				

				while(rs1.next()) {

					Menu m = new Menu();			

					

					m.setMenuid(rs1.getInt("id"));

					m.setMenu(rs1.getString("menu"));					

					

                ///// //     How can i code here ... ////////////

					

				}				

				

				sac.add(c);

			}					

		} finally {

			

		}		

		

		return sac;

	}	

	

}

and my Categories.java:

package com.menu.entities;







public class Categories {

	private int id;

	private String category;	

	

	

	

	public int getId() {

		return id;

	}

	

	public void setId(int id) {

		this.id = id;

	}

	

	public String getCategory() {

		return category;		

	}

	

	public void setCategory(String category) {

		this.category = category;

	}	

}

file Menu.java

package com.menu.entities;



public class Menu {

	private int menuId;

	private String menu;

	

	public int getMenuid() {

		return this.menuId;

	}

	

	public void setMenuid(int menuId) {

		this.menuId = menuId;

	}

	

	public String getMenu() {

		return this.menu;

	}

	

	public void setMenu(String menu) {

		this.menu = menu;

	}

}

and index.java

package com.menu;



import java.io.*;

import java.util.*;



import freemarker.template.*;



import javax.servlet.*;

import javax.servlet.http.*;



import com.menu.dao.generic.GenericCategories;

import com.menu.dao.generic.GenericMenu;



public class Index extends HttpServlet {

private Configuration cfg;

	

	public void init() {

		cfg = new Configuration();

		cfg.setServletContextForTemplateLoading(getServletContext(), "templates");

		cfg.setObjectWrapper(ObjectWrapper.BEANS_WRAPPER);

	}	

	

	public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

		res.setContentType("text/html");

		res.setCharacterEncoding("utf-8");

		Template t = cfg.getTemplate("demo.html");

		

		Map root = new HashMap();		

		

		GenericCategories gc = new GenericCategories();

		GenericMenu gm = new GenericMenu();	

		

		

		try {			

			root.put("allCategories", gc.SelectAllC());

		} catch (Exception e1) {

			System.out.println(e1);

		}		

		

		Writer out = res.getWriter();

		try {

			t.process(root, out);

		} catch (TemplateException te) {

			te.printStackTrace();

		}

	}

}

I want list categories two level, i need you help, thank you very much ...

An idea is to declare another sub arraylist for storing menu items, and then put the sub arraylist into the your sac list.
Add something in the following

//line 41

List sublist = new ArrayList();



//line 48

sublist.add(m);



//line 53

sac.add(sublist);

I tried .... and it does not run

Some hints for you:
1. Change your demo.html as follows:

<#list allCategories as cat>

	${cat.category}


	<#list cat.getMenus() as menu>

	${menu.menu}


	</#list>

</#list>

2.Add a collection object like ArrayList for menus in Categories class

package com.menu.entities;



public class Categories {

	private int id;

	private String category;

	private List menus = new ArrayList();	

	

	public int getId() {

		return id;

	}

	

	public void setId(int id) {

		this.id = id;

	}

	

	public String getCategory() {

		return category;		

	}

	

	public void setCategory(String category) {

		this.category = category;

	}

  

	public List getMenus() {

	    retrun menus;

	}

  

	public void addMenu(Menu menu) {

	    this.menus.add(menu);

	}	

}

Wow, thank you very much andowson