I already compiled, run the program..and it's succesfully done. But when i try to preview using appletviewer, the error below appeared in my prompt.
How to solve the matters below?Thank you

C:\j2sdk1.4.2_10\bin>java HelloWorldApp
Hello World!

C:\j2sdk1.4.2_10\bin>appletviewer HelloWorldApp.html
load: HelloWorldApp.class is not public or has no public constructor.
java.lang.IllegalAccessException: Class sun.applet.AppletPanel can not access a
member of class HelloWorldApp with modifiers ""
at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:57)
at java.lang.Class.newInstance0(Class.java:302)
at java.lang.Class.newInstance(Class.java:261)
at sun.applet.AppletPanel.createApplet(AppletPanel.java:619)
at sun.applet.AppletPanel.runLoader(AppletPanel.java:548)
at sun.applet.AppletPanel.run(AppletPanel.java:299)
at java.lang.Thread.run(Thread.java:534)