IBatis查询条件为多个参数时怎么配置

1） 用String代替

String sql = "uid = '" + username + "' and pwd='" + password + "'";
Integer r = (Integer) sqlMap.queryForObject("checkLogin", sql);

<select id="checkLogin" parameterClass="java.lang.String" resultClass="java.lang.Integer">
     SELECT count(*) AS value FROM userinfo WHERE $sql$
</select>

2）用 Map

Map map=new HashMap();
map.put("uid", username);
map.put("pwd", password);
Integer r = (Integer) sqlMap.queryForObject("checkLogin2", map);

  一种写法：

<select id="    " parameterClass="java.util.Map" resultClass="java.lang.Integer">
       SELECT count(*) AS value FROM userinfo WHERE uid=#uid# and pwd=#pwd#
</select>

  另一种写法

<parameterMap class="java.util.HashMap" id="parameterMap">      
	<parameter property="uid"/>      
	<parameter property="pwd"/> 
</parameterMap>    
<select id="checkLogin2" resultClass="java.lang.Integer" parameterMap="parameterMap">      
	 SELECT count(*) AS value FROM userinfo WHERE uid=? and pwd=?
</select> 

3）用bean

public Student queryStudentsByNameAndId(HashMap<String,String> hashMap)      {         

 Student s=null;          
try {             
      s=(Student)sqlMapClient.queryForObject("selectStudentByIdAndName",hashMap);                       
 } catch (SQLException e) {               
      e.printStackTrace();         
 }         
      return s;     
 }   

<parameterMap class="java.util.HashMap" id="parameterMap">      
      <parameter property="sid"/>      
      <parameter property="sname"/> 
 </parameterMap>    

<select id="selectStudentByIdAndName" resultClass="Student" parameterMap="parameterMap">      
       select * from student where  sid=? and sname=?  
</select>