jsp 多条件组合查询

 ???public String query(HttpServletRequest request, HttpServletResponse response) ???????????throws ServletException, IOException { ???????/* ????????* 1. 封装表单数据到Customer对象中，它只有四个属性（cname、gender、cellphone、email） ????????* ??它就是一个条件 ????????* 2. 使用Customer调用service方法，得到List<Customer> ????????* 3. 保存到request域中 ????????* 4. 转发到list.jsp ????????*/ ???????Customer criteria = CommonUtils.toBean(request.getParameterMap(), Customer.class); ???????List<Customer> cstmList = customerService.query(criteria); ???????request.setAttribute("cstmList", cstmList); ???????return "/list.jsp"; ???}

 ???/** ????* 多条件组合查询 ????* @param criteria ????* @return ????*/ ???public List<Customer> query(Customer criteria) { ???????return customerDao.query(criteria); ???}

/** * 领域对象 与表单和数据库表对应 * ?* @author cxf * ?*/public class Customer { ???/* ????* 对应数据库表 ????*/ ???private String cid;// 主键 ???private String cname;// 客户名称 ???private String gender;// 客户性别 ???private String birthday;// 客户生日 ???private String cellphone;// 客户手机 ???private String email;// 客户邮箱 ???private String description;// 客户的描述 ???public String getCid() { ???????return cid; ???} ???public void setCid(String cid) { ???????this.cid = cid; ???} ???public String getCname() { ???????return cname; ???} ???public void setCname(String cname) { ???????this.cname = cname; ???} ???public String getGender() { ???????return gender; ???} ???public void setGender(String gender) { ???????this.gender = gender; ???} ???public String getBirthday() { ???????return birthday; ???} ???public void setBirthday(String birthday) { ???????this.birthday = birthday; ???} ???public String getCellphone() { ???????return cellphone; ???} ???public void setCellphone(String cellphone) { ???????this.cellphone = cellphone; ???} ???public String getEmail() { ???????return email; ???} ???public void setEmail(String email) { ???????this.email = email; ???} ???public String getDescription() { ???????return description; ???} ???public void setDescription(String description) { ???????this.description = description; ???} ???@Override ???public String toString() { ???????return "Customer [cid=" + cid + ", cname=" + cname + ", gender=" ???????????????+ gender + ", birthday=" + birthday + ", cellphone=" ???????????????+ cellphone + ", email=" + email + ", description=" ???????????????+ description + "]"; ???}}

 /** ????* 多条件组合查询 ????* @param criteria ????* @return ????*/ ???public List<Customer> query(Customer criteria) { ???????try { ???????????/* ????????????* 1. 给出sql模板 ????????????* 2. 给出参数 ????????????* 3. 调用query方法，使用结果集处理器：BeanListHandler ????????????*/ ???????????/* ????????????* 一、　给出sql模板 ????????????* 二、　给出参数！ ????????????*/ ???????????/* ????????????* 1. 给出一个sql语句前半部 ????????????*/ ???????????StringBuilder sql = new StringBuilder("select * from t_customer where 1=1"); ???????????/* ????????????* 2. 判断条件，完成向sql中追加where子句 ????????????*/ ???????????/* ????????????* 3. 创建一个ArrayList，用来装载参数值 ????????????*/ ???????????List<Object> params = new ArrayList<Object>(); ???????????String cname = criteria.getCname(); ???????????if(cname != null && !cname.trim().isEmpty()) { ???????????????sql.append(" and cname like ?"); ???????????????params.add("%" + cname + "%"); ???????????} ???????????????????????String gender = criteria.getGender(); ???????????if(gender != null && !gender.trim().isEmpty()) { ???????????????sql.append(" and gender=?"); ???????????????params.add(gender); ???????????} ???????????????????????String cellphone = criteria.getCellphone(); ???????????if(cellphone != null && !cellphone.trim().isEmpty()) { ???????????????sql.append(" and cellphone like ?"); ???????????????params.add("%" + cellphone + "%"); ???????????} ???????????????????????String email = criteria.getEmail(); ???????????if(email != null && !email.trim().isEmpty()) { ???????????????sql.append(" and email like ?"); ???????????????params.add("%" + email + "%"); ???????????} ???????????????????????/* ????????????* 三、执行query ????????????*/ ???????????return qr.query(sql.toString(), ????????????????????new BeanListHandler<Customer>(Customer.class), ????????????????????params.toArray()); ???????} catch(SQLException e) { ???????????throw new RuntimeException(e); ???????} ???}