thymeleaf常用命名空间：

xmlns:th=http://www.thymeleaf.org
xmlns:sec=http://www.thymeleaf.org/extras/spring-security
xmlns:shiro=http://www.pollix.at/thymeleaf/shiro

html lang=en xmlns:th=http://www.thymeleaf.org 
				xmlns:sec=http://www.thymeleaf.org/extras/spring-security
				xmlns:shiro=http://www.pollix.at/thymeleaf/shiro