SSH_框架整合5--验证用户名是否可用

SSH_框架整合5--验证用户名是否可用

1 emp-input.jsp中编写ajax验证用户名是否可用：　

 <script type="text/javascript" SRC="scripts/jquery-1.7.2.js"></script>
 <script type="text/javascript">
 $(function(){
     $(":input[name=lastName]").change(function(){
             var val = $(this).val();
             val = $.trim(val);
             var $this = $(this);

             if(val != ""){
                 //把当前节点后面的所有 font 兄弟节点删除
                 $this.nextAll("font").remove();

                 var url="emp-validateLastName";
                 var args={"lastName":val,"time":new Date()};
                 $.post(url,args,function(data){
                     //姓名可用
                     if(data == "1"){
                         $this.after("<font color='green'>LastName可用!</font>");
                     }
                     //不可用
                     else if(data == "0"){
                         $this.after("<font color='red'>LastName不可用!</font>");
                     }
                     //服务器错误
                     else{
                         alert("服务器错误!");
                     }
                 });
             }else{
                 alert("lastName不能为空！");
                 $(this).val("");
                 //$(this).focus();
             }
         });
     })
 </script>

2  完善类：底层编写代码实现验证的方法：

　　(1)EmployeeDao.java

 //4 校验注册的姓名是否可用
     public Employee getEmployeeByLastName(String lastName){
         String hql = "FROM Employee e WHERE e.lastName = ?";
         Query query = getSession().createQuery(hql).setString(0, lastName);
         Employee employee = (Employee) query.uniqueResult();
         //System.out.println("***"+employee.getDepartment().getClass().getName());
         return employee;
     }

　　(2)EmployeeService.java

 //4 校验注册的姓名是否可用
     public boolean lastNameIsValid(String lastName){
         //在数据库中查完结果为null，说明没有被注册过
         return employeeDao.getEmployeeByLastName(lastName) == null;
     }

　　(3)EmployeeAction.java　　

 //5 校验注册的姓名是否可用
     private String lastName;

     public void setLastName(String lastName) {
         this.lastName = lastName;
     }

     public String validateLastName() throws UnsupportedEncodingException{
         if(employeeService.lastNameIsValid(lastName)){
             inputStream = new ByteArrayInputStream("1".getBytes("UTF-8"));
         }else{
             inputStream = new ByteArrayInputStream("0".getBytes("UTF-8"));
         }
         return "ajax-success";
     }
     

　　其中delete()方法的return修改为：return "ajax-success";

3 applicationContext.xml中修改为只读：

　　<tx:method name="lastNameIsValid" read-only="true"/>