type erasure in implementation of ArrayList in Java

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1

I was reading this article on Java Generics and there it is mentioned that the constructor for arrayList looks somewhat like this:

class ArrayList<V> {
  private V[] backingArray;
  public ArrayList() {
    backingArray = (V[]) new Object[DEFAULT_SIZE]; 
  }
}

I was not able to understand how type erasure and type checking by compiler happens as explained there. One point though I got was the type parameter is transformed to Object type.

so I would imagine it as (replacing all V with Object). but this definitely wrong.

class ArrayList<Object> {
      private Object[] backingArray;
      public ArrayList() {
        backingArray = (Object[]) new Object[DEFAULT_SIZE]; 
      }
    }

How exactly is it transformed to Object type but still retaining the type safety for V? when I have ArrayList and ArrayList are there two different classes for each? if not where the type information of String and Integer is stored?

asked 1 min ago

brain storm

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