两个lader对象共享bottom
class Lader{
double above,height;
static double bottom;
void setAbove(double a){
above=a;
}
void setBottom(double b){
bottom=b;
}
double getAbove(){
return above;
}
double getBottom(){
return bottom;
}
}
class Example4_4{
public static void main(String args[]){
Lader.bottom=60;
Lader laderOne,laderTwo;
System.out.println("now all Lader's bottom;"+Lader.bottom);
laderOne=new Lader();
laderTwo=new Lader();
System.out.println("laderOne bottom:"+laderOne.getBottom());
System.out.println("laderTwo bottom:"+laderTwo.getBottom());
laderOne.setAbove(11);
laderTwo.setAbove(22);
laderTwo.setBottom(100);
System.out.println("now all Lader's bottom;"+Lader.bottom);
System.out.println("laderOne above :"+laderOne.getAbove());
System.out.println("laderTwo above :"+laderTwo.getAbove());
}
}