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Generics strange behavior

Generics strange behavior

(OP)
Hi everyone!

I've noticed an strange behavior when using Generic types, o maybe there's something missing that i don't know, after all i'm newbie dealing with generics:

CODE

import java.util.PriorityQueue;
import java.util.Random;

public class Erlang {
  public static void main(String[] args){
    Random unif=new Random();
    PriorityQueue<Event> list=new PriorityQueue<Event>();
    list.add(new Event(unif.nextDouble(), Type.ARRIVAL));
  }
}
where Event is a class well defined in Event.java and Type.ARRIVAL is a static final form class Type in Type.java
This piece of code works fine, but the devil appears with the following modification:

CODE

import java.util.PriorityQueue;
import java.util.Random;

public class Erlang {
  public static void main(String[] args){
    Random unif=new Random();
    PriorityQueue<Event> list=new PriorityQueue<Event>();
    for(int i=0; i<10; i++)
      list.add(new Event(unif.nextDouble(), Type.ARRIVAL));
  }
}
when the program reaches list.add(new Event(blah blah...)); in the for statement i get a:

CODE

Exception in thread "main" java.lang.ClassCastException: Eventt
    at java.util.PriorityQueue.fixUp(Unknown Source)
    at java.util.PriorityQueue.offer(Unknown Source)
    at java.util.PriorityQueue.add(Unknown Source)
    at Erlang.main(Erlang.java:9)

any idea of why i get this exception?

any help would be appreciated
:D

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