protected Class<? extends WebEnvironment> getDefaultWebEnvironmentClass(ServletContext ctx) {
        return IniWebEnvironment.class;
    }
Returns the default WebEnvironment class, which is unless overridden: {@link IniWebEnvironment}.

@param ctx servlet context
@return the default WebEnvironment class.
web/src/main/java/org/apache/shiro/web/env/EnvironmentLoader.java