class blabla extends JPanel
{
public blabla()
{
//code
}
}
class Main
{
public static void main(String[] args)
{
JPanel b;
ArrayList<blabla> c;
blabla a = new blabla();
b = new JPanel();
c = new ArrayList<blabla>();
b.add(a);
c.add(a);
blabla d = (blabla) b.getComponent(0);
System.out.println(c.indexOf(d));
}
}
是ArrayList a
和JPanel a
相同的对象吗?代码输出应该是什么?