My applet is in the root of my application-----myapp/ But it will call a class in another package which will also be imported by the classes in the WEB-INF/classes.So I make that package into a jar file and put tha jar in the WEB-INF/lib. When I run myapp, the applet can't work correctly,but the class in the WEB-INF/classes work well.Why? If the applet can't call the classes in the WEB-INF/lib or WEB-INF/classes, how can I achieve the following function: the applet and the class in the WEB-INF/classes can call a class file together? Thank you!!!