java 设置嵌套泛型

class Info<T,V>{
    private T var;
    private V value;
    public Info(T var,V value){
        this.setVar(var);
        this.setValue(value);
    }
    public T getVar() {
        return var;
    }
    public void setVar(T var) {
        this.var = var;
    }
    public V getValue() {
        return value;
    }
    public void setValue(V value) {
        this.value = value;
    }
    
}
class Demo<S>{
    private S info;
    public Demo(S info){
        this.setInfo(info);
    }
    public S getInfo() {
        return info;
    }
    public void setInfo(S info) {
        this.info = info;
    }
}
public class GenericsDemo {
        public static void main(String[] args) {
            Demo<Info<String,Integer>> d=null;
            Info<String,Integer> i=null;
            i=new Info<String,Integer>("Lixinghua",30);//注意此处
            d=new Demo<Info<String,Integer>>(i);//注意此处
            System.out.println("content1:"+d.getInfo().getVar());
            System.out.println("content2:"+d.getInfo().getValue());
        }
}