Java generics and casting to a primitive type

Question

I am currently trying to learn how to use Generics from a book. In this chapter it says to take a piece of data T and convert it to an integer. I am trying different things

Answer 1

try to observe below examples:

public static void main(String[] args) {
    test0("13");
    test0(new Integer(13));
    test1();
    System.out.println(findValue(new Node("10")));
}

private static  void test0(T a) {
    LinkedList arr = new LinkedList();
    arr.add((T) a);
    System.out.println(arr.getFirst());
}

private static  void test1() {
    LinkedList arr = new LinkedList();
    arr.add((T) new Integer(13));
    System.out.println(arr.getFirst());
}

public static  int findValue(Node node) {
    T data = (T) node.data;
    int value = Integer.valueOf(data.toString());
    return value;
}

where Node is :

    public class Node {

    //this should be private
        public String data;

        public Node(String data) {
            this.data = data;
        }

    //use getter below to access private data
    public String getData() {
            return data;
        }

  }

all this is possible because, unchecked casts from a known type to T is allowed (of course with warnings) and compiler believes you for the casting.