业务层接口和实现：

public interface BussinessService {

 /**  * 查询所有客户信息  *   */ @Deprecated List<Customer> findAll(); /**  * 增加客户信息  *  c  */ void addCustomer(Customer c); /**  * 根据主键删除客户信息  *  customerId  */ void delCustomer(String customerId); /**  * 分居主键查询客户信息  *  customerId  *  null  */ Customer findCustomerById(String customerId); /**  * 更新客户信息  *  c  *  CustomerIdCannotBeEmpty  */ void updateCustomer(Customer c) throws CustomerIdCannotBeEmpty; /**  * 输入页码，  *  pageNum  *  返回pange对象  */ Page findPage(String num);}

public class BussinessServletImpl implements BussinessService {

  private CustomerDao dao=new CustomerDaoImpl(); @Deprecated public List<Customer> findAll() {   return dao.findAll(); }

 public void addCustomer(Customer c) {

  c.setId(UUID.randomUUID().toString());  dao.add(c); }

 public void delCustomer(String customerId) {

  dao.delete(customerId); }

 public Customer findCustomerById(String customerId) {

  return dao.findById(customerId); }

 public void updateCustomer(Customer c) throws CustomerIdCannotBeEmpty {

  if(c.getId()==null){    throw new CustomerIdCannotBeEmpty("参数有误，请输入正确的客户信息");  }  dao.update(c); }

 public Page findPage(String num) {

  int pageNum=1;//默认值为1  if(num!=null){    pageNum=Integer.parseInt(num);  }  int totalRecords=dao.getTotalRecordsNum();  Page page=new Page(pageNum, totalRecords);  List<Customer> records=dao.findPageCustomers(page.getStartIndex(), page.getPageSize());  page.setRecords(records);  return page; }

}

数据控制servlet:

public class Controller extends HttpServlet {

 private BussinessService bs=new BussinessServletImpl(); public void doGet(HttpServletRequest request, HttpServletResponse response)   throws ServletException, IOException {   request.setCharacterEncoding("UTF-8");  response.setContentType("text/html;charset=UTF-8");  String op=request.getParameter("op");  if("showAllCustomers".equals(op)){    showAllCustomers(request,response);  }else if("addCustomer".equals(op)){    addCustomer(request,response);  }else if("editCustomerUI".equals(op)){    editCustomerUI(request,response);  }else if("editCustomer".equals(op)){    editCustomer(request,response);  }else if("delOneCustomer".equals(op)){    delOneCustomer(request,response);  }else if("delMulti".equals(op)){    delMulti(request,response);  } }

 

 private void delMulti(HttpServletRequest request,

   HttpServletResponse response) throws IOException  {   String ids[]=request.getParameterValues("ids");  if(ids!=null&&ids.length>0){    for(int i=0;i<ids.length;i++){     bs.delCustomer(ids[i]);   }  }  response.sendRedirect(request.getContextPath()); }

 

 private void delOneCustomer(HttpServletRequest request,

   HttpServletResponse response) throws IOException {   String customerId=request.getParameter("customerId");  bs.delCustomer(customerId);  response.sendRedirect(request.getContextPath()); }   private void editCustomer(HttpServletRequest request,   HttpServletResponse response) throws ServletException, IOException{     //将信息封装到formBean    CustomerFormBean formBean=WebUtil.fillBean(request, CustomerFormBean.class);    //信息不正确，数据回显    if(!formBean.validate()){      request.setAttribute("formBean", formBean);     request.getRequestDispatcher("/addCustomer.jsp").forward(request, response);    }    //填充模型，注意类型转化     ConvertUtils.register(new DateLocaleConverter(),Date.class);    Customer c=new Customer();    try {      BeanUtils.copyProperties(c, formBean);    } catch (Exception e) {      throw new RuntimeException("填充模型时出现异常");    }     //单独处理爱好选项    String preference[]=request.getParameterValues("preference");    if(preference!=null&&preference.length>0){      StringBuffer sb=new StringBuffer();     for(int i=0;i<preference.length;i++){       if(i>0){        sb.append(",");      }      sb.append(preference[i]);     }     c.setPreference(sb.toString());    }    //保存数据    try {      bs.updateCustomer(c);    } catch (CustomerIdCannotBeEmpty e) {      e.printStackTrace();    }    //用重对象将页面跳转到默认主页，防止重复提交    response.sendRedirect(request.getContextPath()); }

 

 private void editCustomerUI(HttpServletRequest request,

   HttpServletResponse response) throws ServletException, IOException {   String customerId=request.getParameter("customerId");  Customer c=bs.findCustomerById(customerId);  request.setAttribute("c", c);  request.getRequestDispatcher("/editCustomer.jsp").forward(request, response); } private void addCustomer(HttpServletRequest request,   HttpServletResponse response) throws IOException, ServletException  {   //将信息封装到formBean  CustomerFormBean formBean=WebUtil.fillBean(request, CustomerFormBean.class);  //信息不正确，数据回显  if(!formBean.validate()){    request.setAttribute("formBean", formBean);   request.getRequestDispatcher("/addCustomer.jsp").forward(request, response);  }  //填充模型，注意类型转化   ConvertUtils.register(new DateLocaleConverter(),Date.class);  Customer c=new Customer();  try {    BeanUtils.copyProperties(c, formBean);  } catch (Exception e) {    throw new RuntimeException("填充模型时出现异常");  }   //单独处理爱好选项  String preference[]=request.getParameterValues("preferences");  if(preference!=null&&preference.length>0){    StringBuffer sb=new StringBuffer();   for(int i=0;i<preference.length;i++){     if(i>0){      sb.append(",");    }    sb.append(preference[i]);   }   c.setPreference(sb.toString());  }  //保存数据  bs.addCustomer(c);  //用重对象将页面跳转到默认主页，防止重复提交  response.sendRedirect(request.getContextPath()); }

 private void showAllCustomers(HttpServletRequest request,

   HttpServletResponse response) throws ServletException, IOException{   List<Customer> cs=bs.findAll();  request.setAttribute("cs", cs);  String num=request.getParameter("num");  Page page=bs.findPage(num);  page.setServletUrl("/servlet/Controller?op=showAllCustomers");  request.setAttribute("page", page);  request.getRequestDispatcher("/listCustomers.jsp").forward(request, response); }

 public void doPost(HttpServletRequest request, HttpServletResponse response)

   throws ServletException, IOException {   doGet(request, response); }

}