jsp页面

三级联动+数据库

sanjilist = sanjiDao.getSanjilistBySql(sql1);

session.setAttribute("provinces", sanjilist);

%>

省：请选择...

${ province.name}

市：请选择...

县：请选择...

servlet;

package servlet;

import java.io.IOException;

import java.io.PrintWriter;

import java.lang.reflect.Method;

import java.sql.SQLException;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import com.fasterxml.jackson.databind.ObjectMapper;

import dao.SanjiDao;

import entity.Sanji;

/**

* 三级联动servelt

* @author asus pc

*

*/

public class SanjiServlet extends HttpServlet {

SanjiDao sanjiDao = new SanjiDao();

public void destroy() {

super.destroy(); // Just puts "destroy" string in log

// Put your code here

}

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

request.setCharacterEncoding("utf-8");

response.setContentType("text/html;charset=UTF-8");

String methodname=request.getParameter("method");

try {

Method method=getClass().getDeclaredMethod(methodname,HttpServletRequest.class,HttpServletResponse.class);

method.invoke(this, request,response);//调用各自的方法

} catch (Exception e) {

e.printStackTrace();

}

}

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

HttpSession session = request.getSession();

/**

//接收父级code

String parentCode="01";

//根据不同联动的code，查询下一级

String sql="SELECT name,code,parentCode from danyuan where parentCode='"+parentCode+"'";

Listsanjilist = sanjiDao.getSanjilistBySql(sql);

for (Sanji sanji : sanjilist) {

System.out.println("sanji.getName()=+++++"+sanji.getName());

}

*/

}

protected void city(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException, ClassNotFoundException, SQLException {

System.out.println("city的servlet进入了");

String province_code=request.getParameter("province_code");

String sql="SELECT name,code,parentCode from danyuan where parentCode='"+province_code+"'";

Listcities=sanjiDao.getSanjilistBySql(sql);

ObjectMapper mapper=new ObjectMapper();

String result=mapper.writeValueAsString(cities);

System.out.println("city_result="+result);

response.setContentType("text/javascript");

response.getWriter().print(result);

}

protected void county(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException, ClassNotFoundException, SQLException {

System.out.println("county的servlet进入了");

String city_code=request.getParameter("city_code");

String sql="SELECT name,code,parentCode from danyuan where parentCode='"+city_code+"';";

Listcounties=sanjiDao.getSanjilistBySql(sql);

ObjectMapper mapper=new ObjectMapper();

String result=mapper.writeValueAsString(counties);

System.out.println("country_result="+result);

response.setContentType("text/javascript");

response.getWriter().print(result);

}

public void init() throws ServletException {

// Put your code here

}

}dao:

package dao;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

import util.ConnectSql;

import entity.Saler_Role;

import entity.Sanji;

/**

* 三级联动的方法

* @author asus pc

*

*/

public class SanjiDao {

ConnectSql connetSql =new ConnectSql();

PreparedStatement ps =null;

ResultSet rs=null;

/**

*根据不同sql语句， 获得联动列表

*/

public List getSanjilistBySql(String sql){

List sanjilist = new ArrayList();

connetSql.ConnectSql();

rs= connetSql.Querry(sql);

try {

while(rs.next()){

Sanji sanji = new Sanji();

sanji.setName(rs.getString("name"));

sanji.setCode(rs.getString("code"));

sanji.setParentCode(rs.getString("parentCode"));

//System.out.println(rs.getInt(1)+rs.getString(2)+rs.getString(3)+rs.getInt(4));

sanjilist.add(sanji);

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

connetSql.CloseCon();

return sanjilist;

}

}