mybatis里if标签判断字符串相等不相等的问题

<foreach collection="accurateSearchMap" index="key" item="item">
	    		<if test="key == 'gcc.sex' and item != '3' and item!='' and item!=null">
	    			and	${key}  = #{item}
	    		</if>
	    		<if test="key == 'gcc.classes' and item != '3' and item!='' and item!=null">
	    			and	${key}  = #{item}
	    		</if>
	    		<if test="key == 'gcc.add_target' and item != '2' and item!='' and item!=null">
	    			and	${key}  = #{item}
	    		</if>
	    		<if test="key == 'gcc.custype' and item != '3' and item!='' and item!=null">
	    			and	${key}  = #{item}
	    		</if>
	    		<if test="item!='' and item!=null and key != 'gcc.sex' and key != 'gcc.classes' and key != 'gcc.add_target' and key != 'gcc.custype'">
	    		    and ${key}  = #{item}
	    		</if>
	    	</foreach>

因为accurateSearchMap是Map<String, Object>类型的，所以键对应的值是Object类型的，而对象间用==或!=比较的是地址引用，所以在值为Object类型的情况下以上代码是有问题的。
解决办法是：在值item后加上toString方法的调用，'1'后面也要加toString方法的调用