代码如下:
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
public class FanXingT<T> {
private T over;
public T getOver() {
return over;
}
public void setOver(T over) {
this.over = over;
}
public static void main(String args[]) {
FanXingT f = new FanXingT();
f.setOver(1);
System.out.println(f.getOver());
f.setOver(1.55);
System.out.println(f.getOver());
Set s = new HashSet();
s.add(1);
s.add("a");
s.add('c');
f.setOver(s);
Iterator it = s.iterator();
while(it.hasNext()) {
System.out.println(it.next());
}
}
}
可以看到我在实例化FanXingT时并没有指定T的类型,那还需要通配符?干嘛呢?