Java generics - getting the type

Question

Duplicate: Instantiating generics type in java

Hi! I'm a c# guy giving Java a try .. so how would I do the following in java.

in C#

public T create_an_instance_of<T>(){
  T instance = default (T);
 // here's usually some factory to create the implementation
   instance =  some_factory.build<T>();
 // or even..
   instance = some_factory.build(typeOf(T) );

 return instance;
}

Answer 1

Java's generics are based on type erasure. That allows them to be downwards-compatible, but means that you cannot use the type parameter itself, because it does not exist at runtime.

The closest thing you can do is this:

public <T> T create_an_instance_of(Class<T> c){
    return c.newInstance(); // or use constructors via reflection
}