现有: 1. class Top { 2 . static int x=l ; 3. public Top (inty) { x*=3; } 4. } 5. class Middle extends Top { 6. public Middle() {x+=1; ) 7. public static void main (String [] args) { 8. Middle m = new Middle(); 9. System. out .println (x); IO. } II. } 结果为: