req.setCharacterEncoding("UTF-8");

resp.setCharacterEncoding("UTF-8");

        String name = req.getParameter("name");

        String deptName = req.getParameter("deptName");

        name = new String(name.getBytes("ISO-8859-1"), "UTF-8");

        deptName = new String(deptName.getBytes("ISO-8859-1"), "UTF-8");

package servlet;

import Dao.DeptDao;

import Dao.EmpDao;

import entity.Emp;

import org.json.JSONArray;

import org.json.JSONException;

import org.json.JSONObject;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.io.IOException;

import java.io.PrintWriter;

import java.io.UnsupportedEncodingException;

public class EmpServlet extends HttpServlet{

    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String action = req.getParameter("action");

        req.setCharacterEncoding("UTF-8");

        resp.setCharacterEncoding("UTF-8");

        if("listEmp".equals(action)){

            listEmp(req,resp);

        }

    }

    private void listEmp(HttpServletRequest req, HttpServletResponse resp){

        JSONArray result = EmpDao.listEmp();

        PrintWriter pw = null;

        try {

            pw = resp.getWriter();

            pw.println(result);

            pw.flush();

            pw.close();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String action = req.getParameter("action");

        req.setCharacterEncoding("UTF-8");

        resp.setCharacterEncoding("UTF-8");

        if("addEmp".equals(action)){

            try {

                addEmp(req,resp);

            } catch (JSONException e) {

                e.printStackTrace();

            }

        }

    }

    private void addEmp(HttpServletRequest req, HttpServletResponse resp) throws JSONException, UnsupportedEncodingException {

        String name = req.getParameter("name");

        String deptName = req.getParameter("deptName");

        name = new String(name.getBytes("ISO-8859-1"), "UTF-8");

        deptName = new String(deptName.getBytes("ISO-8859-1"), "UTF-8");

        int deptId = DeptDao.reConvert(deptName);

        JSONObject result = EmpDao.addEmp(name,deptId);

        try {

            PrintWriter pw = resp.getWriter();

            pw.println(result);

            pw.flush();

            pw.close();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

}