Mybatis进行id类型、String类型、map类型、ben类型参数传入Sql查询

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用习惯了Hibernate，再换成Mybatis总会遇到一些变态问题，正如下面的错误提示，用mybatis查询时，传入一个字符串传参数，且进行判断时，会报 错误

There is no getter for property named 'moduleCode' in 'class java.lang.String  
           

Dao层调用方式

/*
 *  Dao层查询 
 */
@Override
public List<CityFace> findCityFaceByCondition(String eqDate) {
	return sqlSession.selectList(CityFace.class.getName()+"_Mapper.findCityFaceByCondition",eqDate); 
}
           

常见的错误写法：XML映射Sql

<select id="findCityFaceByCondition" parameterType="String" resultType="CityFace">
	select * from (select unitname, to_char(rdate,'yyyy-MM') rdate,analysistype, scope from CITYSCAPEANALYSIS) 
	pivot (sum(scope) for analysistype in ('ESScope' esscope, 'EOScope' eoscope,'GCScope' gcscope, 'CScope' cscope))  
	<if test='eqDate!=""'>
		where rdate = #{eqDate}
	</if>
</select>
           

需要修改成： 

<select id="findCityFaceByCondition" parameterType="String" resultType="CityFace">
	select * from (select unitname, to_char(rdate,'yyyy-MM') rdate,analysistype, scope from CITYSCAPEANALYSIS) 
	pivot (sum(scope) for analysistype in ('ESScope' esscope, 'EOScope' eoscope,'GCScope' gcscope, 'CScope' cscope))  
	<if test='_parameter!=""'>
		where rdate = #{_parameter}
	</if>
</select>
           

不管你的参数是什么，都要改成"_parameter"，但是ID就不用改就行

Java调用ID示例

@Override
public Visitlogs findVisitlogsById(int id) {
	return sqlSession.selectOne(Visitlogs.class.getName()+"_Mapper.findVisitlogsById", id);
}
           

xml映射

<!-- 根据id查询用户 -->
<select id="findVisitlogsById" parameterType="int" resultMap="resultVisitlogs">
	select * from visitlogs where id=#{id}
</select>
           

———————————————————————————分割线————————————————————————————

上面说的是String单个值，如果是多个值就可以使用map对象和Bean类对象进行封装，然后就可以使用常用的方式接收了，比如下面的案例

Java调用Map示例

@Override
public AppUser loginUser(String userName, String password) {
	Map<String, String> map = new HashMap<String, String>();
	map.put("name", userName);
	map.put("password", password);
	return sqlSession.selectOne(AppUser.class.getName()+"_Mapper.loginUser", map);
}
           

xml映射

<!-- 登录用户 -->
<select id="loginUser" parameterType="map" resultType="AppUser">
	select * from app_user where name=#{name} and password=#{password}
</select>
           

Java调用Bean类示例

@Override
public AppUser loginUser(String userName, String password) {
	AppUser user = new AppUser();
	user.setName(userName);
	user.setPassword(password);
	return sqlSession.selectOne(AppUser.class.getName()+"_Mapper.loginUser", user);
}
           

xml映射

<!-- 登录用户 -->
<select id="loginUser" parameterType="AppUser" resultType="AppUser">
	select * from app_user where name=#{name} and password=#{password}
</select>