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"/>