javaweb增刪改查（二）

員工列表增刪改查


UpdateEmpViewServlet和UpdateServlet區別
點擊修改按鈕—進入的就是updateempview頁面—要根據頁面顯示的數據進行修改
1.獲取到id
2.因爲根據id查詢數據
3.把查詢的數據綁定到req對象上
4.遍歷循環再綁定所屬部門的數據
5…轉發到修改頁—updateemp，jsp
UpdateEmpViewServlet

@WebServlet(urlPatterns = ("/updateempview"))
public class UpdateEmpViewServlet extends HttpServlet {

    private EmpService empService = new EmpServiceImpl();

    private DeptService deptService = new DeptServiceImpl();
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        //獲取到id
        Integer empId = Integer.parseInt(req.getParameter("id"));

        //根據id查詢數據

        Emp emp = empService.getEmpById(empId);
        //綁定到req對象
        req.setAttribute("emp",emp);

        //再綁定所屬部門數據
        List<Dept> deptList = deptService.listDept();
        req.setAttribute("deptList",deptList);


        //轉發到修改頁
        req.getRequestDispatcher("/WEB-INF/pages/updateemp.jsp").forward(req,resp);


    }
}

UpdateServlet
1.顯示數據
2.創建一個新對象，存儲數據
3.重定向到emplist頁面

WebServlet(urlPatterns = ("/updateemp"))
public class UpdateServlet extends HttpServlet {

    private EmpService empService = new EmpServiceImpl();

    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("utf-8");
        Integer empId = Integer.parseInt(req.getParameter("empId"));
        String name = req.getParameter("name");
        Integer age = Integer.parseInt(req.getParameter("age"));
        String sex = req.getParameter("sex");
        BigDecimal salary =new BigDecimal(req.getParameter("salary"));
        //System.out.println("============================"+req.getParameter("deptId"));
        Integer deptId = Integer.parseInt(req.getParameter("deptId"));


        Emp param = new Emp();
        param.setEmpId(empId);
        param.setName(name);
        param.setAge(age);
        param.setSex(sex);
        param.setSalary(salary);
        param.setDeptId(deptId);
        
        empService.updateEmp(param);
        //重定向到emplist頁面
        resp.sendRedirect("emplist");
    }
}