上浒充通大学 SJTU School Of Software 2009-2-3 D Hello.iava 1 package example; 2 3vpublic class Hello 4 5 public static void main(String[]args)( 8 99 public int abs(int n){ 10 return n>=0 n (-n) 12 软件学院SJTU School Of Software 2009-2-3 软件学院