Access restriction: The type SAXReader is not accessible due to restriction on r

今天用dom4j解析的时候报了这个错误

Access restriction: The type SAXReader is not accessible due to restriction on required library G:\dom4j-1.6.1\dom4j-1.6.1.jar

解决方法是：

     Windows -> Preferences -> Java -> Compiler -> Errors/Warnings

     (Project) Properties -> Java Compiler -> Errors/Warnings

后来查了下access restriction大概都是这里的问题，要不就是Deprecated API Error-->Waring