Re: how to instantiate new return object of generic type

Daniel Pitts <>
16 Apr 2007 23:50:04 -0700
On Apr 16, 11:29 pm, tom forsmo <> wrote:

Robert Klemme wrote:

On 16.04.2007 14:49, tom forsmo wrote:

You can either use reflection or you define a generic interface for a
factory object that will create a new object from the given instance.
Something along the lines of

interface Factory<V> {
  V create(V template);

Ok, so how do I do actually create the new object and how do I find out
what type of object I am to create?

creation example:

        V val = new String(message);

is not legal, nor is casting it to V since V is unknown.


You have to create a explicit Factory for the types you want to
interface Factory<V> {
   V create(V template);

class Table<K, V> {
   private final Factory<V> factory;
   public Table(Factory<V> factory) {
      this.factory = factory;

   public V get(K key, Locale locale) {
      return factory.create(find(key));

new Table<String, Number>(
   new Factory<Number>() {
       Number create(Number template) {
           return template == null ? Integer.valueOf(0) :

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