import javax.swing.JOptionPane;
public class Displayunicode {
}
如上,javax.swing.JOptionPane;会显示红色波浪线,报错提示为
Access restriction: The type JOptionPane is not accessible due to restriction on required library E:\Program Files\Java\jre8\lib\rt.jar Displayunicode.java /practise/src/practise line 2 Java Problem
但什么环境变量都配置对了啊,IDE是Eclipse最新版本的啊,java版本也是最新的,求解这是为什么啊?