jQuery+jsp实现省市县三级联动效果(附源码)_jquery

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>


 
  
 
 /js/jquery/jquery-1.7.min.js">
 /js/json/json-minified.js">
 
 
 

 

 

 省份：
 
 城市：
 
 请选择
 
 区(县)：
 
 请选择
 
 
 
 
 

public class GetDropdownDataServlet extends HttpServlet {
 public void doGet(HttpServletRequest request, HttpServletResponse response)
 throws IOException, ServletException {
 doPost(request, response);
 }
 public void doPost(HttpServletRequest request, HttpServletResponse response)
 throws IOException, ServletException {
 String parentId = request.getParameter("parentId");
 if (parentId == null || parentId == "") {
 parentId = "0";
 }
 Connection conn = null;
 String json = "";
 try {
 Class.forName("com.mysql.jdbc.Driver");
 conn = DriverManager.getConnection("jdbc:mysql://localhost/dropdown",
 "root", "root");
 Statement stat = conn.createStatement();
 ResultSet rs = stat
 .executeQuery("select region_id,region_name from region where parent_id = "
 + parentId);
 ArrayList rsList = new ArrayList();
 Map map = null;
 while (rs.next()) {
 map = new HashMap();
 map.put("id", rs.getInt(1));
 map.put("name", rs.getString(2));
 rsList.add(map);
 }
 rs = null;
 Gson gson = new Gson();
 json = gson.toJson(rsList);
 System.out.println("json=" + json);
 } catch (ClassNotFoundException e) {
 e.printStackTrace();
 } catch (SQLException e) {
 e.printStackTrace();
 } finally {
 if (conn != null) {
 try {
 conn.close();
 } catch (SQLException e) {
 e.printStackTrace();
 }
 }
 }
 response.setCharacterEncoding("UTF-8");
 response.getWriter().print(json);
 }
}