在方法中设定泛型的上限

/*受限泛型：泛型的上限（设置方法只能接收泛型为Number或Number类型的子类）*/
class Info1<T>{
private T var;


public T getVar() {
return var;
}
public void setVar(T var) {
this.var = var;
}
public String toString(){
return this.var.toString();
}
}
public class GenericsDemo4 {


public static void main(String[] args) {
// TODO Auto-generated method stub
Info1<Integer> i1 = new Info1<Integer>();
Info1<Float> i2 = new Info1<Float>();
i1.setVar(30);
i2.setVar(30.5f);
fun(i1);
fun(i2);
}
public static void fun(Info1<? extends Number> temp){     //指定泛型的上限
System.out.println(temp+"、");
}
}