Namespace in <mapper namespace> turns red
Solution:
The XML file header language should be changed to the mapper mapping instead of the config
previously used as follows:
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
Change to
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
Create folders with different functions