What does the following Java code demonstrate?

public class GenericExample<T> {
    private T data;
    public GenericExample(T data) {
        this.data = data;
    }
    public T getData() {
        return data;
    }
    public static void main(String[] args) {
        GenericExample<Integer> intExample = new GenericExample<>(123);
        System.out.println(intExample.getData());
    }
}