IDEA Usage of API documented as @since 1.6+ 语法错误解决方案

Usage of API documented as @since 1.6+ This inspection finds all usages of methods that have @since tag in their documentation. This may be useful when development is performed under newer SDK version as the target platform for production

 

File ->Project Structure->Project Settings -> Modules -> 你的Module名字 -> Sources -> Language Level->选个默认的就行。