Writing generic interfaces?

Question

I would like to write a generic interface for a Factory. The implemented Factory should as minimum contain two methods that returns a List of "something" as seen below.
But I don't want to put any restrictions on the return type since a user might want to use objects from his or her own API. Is the solution to just specify the interface as:
public interface IReportFactory {
     List newProducts();
     List newTables();
}

Answer 1

Here's a small example to guide you. Good luck my friend...
import java.util.*;
public class Test
     public static void main(String... args)
          List<Product> prodList = new ArrayList<Product>();
          prodList.add(new Product("radio", 100)); prodList.add(new Product("Walkman", 50));
          List<Table> tableList = new LinkedList<Table>();
          tableList.add(new Table("customer", 100)); tableList.add(new Table("Product", 1000));
          Report r = new Report(prodList, tableList);
          System.out.println("Products\n----------\n"+r.newProducts());
          System.out.println("Tables\n----------\n"+r.newTables());
          System.out.println("\nChanging Structures to Vector and Stack\n");
          prodList = new Vector<Product>();
          prodList.add(new Product("radio", 100)); prodList.add(new Product("Walkman", 50));
          tableList = new Stack<Table>();
          tableList.add(new Table("customer", 100)); tableList.add(new Table("Product", 1000));
          r = new Report(prodList, tableList);
          System.out.println("Products\n----------\n"+r.newProducts());
          System.out.println("Tables\n----------\n"+r.newTables());
class Product
     String name; double price;
     Product(String n, int p){ name = n; price = p;}
     public String toString(){ return "\nName = "+name+" & Price = "+price+"\n";}
class Table
     String name; int numRecs;
     Table(String i, int v){ name = i; numRecs = v;}
     public String toString(){ return "\nName = "+name+" & # of Records = "+numRecs+"\n";}
class Report<T, V> implements IReportFactory<T, V>
     T prodList;
     V tableList;
     Report(T prodList, V tableList)
          this.prodList = prodList;
          this.tableList = tableList;
     public T newProducts()
          return this.prodList;
     public V newTables()
          return this.tableList;
interface IReportFactory<T, V>
     T newProducts();
     V newTables();
}