2018-03-04 web用户项目:全查找和条件查找用户信息

笔记如下

1. 全查找实现

• list.jsp

        对不起,当前没有任何的客户信息存在

    

    
                

            

                
客户姓名
                
客户性别
                
客户生日
                
客户邮箱
                
客户手机
                
客户爱好
                
客户类型
                
客户描述
                
操作
            
            

                    
${customer.name}
                    
${customer.gender}
                    
${customer.birthday}
                    
${customer.email}
                    
${customer.cellphone}
                    
${customer.preference}
                    
${customer.type}
                    
${customer.description}
                
            
            
        

• web层(FindAllCustomersServlet)

        CustomerService cs = new CustomerService();
        List customers  =  cs.findAll();
        
        
        
        //转发请求给list.jsp页面
        request.setAttribute("customers", customers);
        request.getRequestDispatcher("/list.jsp").forward(request, response);

• 业务层(CustomerService)

    //查询所有额度客户信息
    public List findAll() {

        //调用dao
    
        return cdao.getAll();
    }

• dao层(CustomerDaoImpl)

//查询所有客户信息
    /* (non-Javadoc)
     * @see com.chen.customers.dao.CustomerDao#getAll()
     */
    @Override
    public List getAll() {
        
        QueryRunner runner = new QueryRunner(JdbcUtils.getDataSource());
        try {
            return runner.query("select * from customers", new BeanListHandler(Customer.class));
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

    }

2.条件查找实现

• list.jsp

                
                        请选择查询条件:
                        
                            
                                
                                        seclected="selected"
                                    
                                >按姓名查询
                                
                                
                                        seclected="selected"
                                    
                                >按手机号查询
                                
                                        seclected="selected"
                                    
                                >按描述查询
                            
                            
                            
                        
        

• web层(ConditionQueryServlet)

//解决乱码
        request.setCharacterEncoding("utf-8");
        
        //获得查询的条件和查询的条件对应的值
        String conditionname = request.getParameter("conditionname");
        String conditionvalue = request.getParameter("conditionvalue");
        
        //调用业务层查询
        CustomerService cs = new CustomerService();
        
        List customers =  cs.conditionQuery(conditionname,conditionvalue);
         
        
        //这里可以复用
        request.setAttribute("customers", customers);
        request.getRequestDispatcher("list.jsp").forward(request, response);

• 业务层(ConditionQueryServlet)

//条件查询
    public List conditionQuery(String conditionname, String conditionvalue) {
        
        return cdao.conditionQuery(conditionname,conditionvalue);
        
    }

• dao层

//条件查询
    @Override
    public List conditionQuery(String conditionname, String conditionvalue) {
        
        QueryRunner runner = new QueryRunner(JdbcUtils.getDataSource());
        
        //条件查询
        
        String sql = "select * from customers where  " + conditionname +" like ?" ;
        
        try {
            return runner.query(sql, new BeanListHandler(Customer.class), "%"+conditionvalue+"%");
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
        
    }

演示:

image.png