Getting a random player/string from ArrayList or Hashmap?

I'm really curious how this works and what I've been thinking is to loop through all the players in the list.

Thought Code:

Code:java

int i = 0;
for(Player p : <list>){
if(i < <list>.length - (<list>.length - 1)){
<list>.add(p.getName());
}
}
//<list> is representing a list. Can be anything.

Would anyone tell me a concept/idea for the code that would be used or a way to get around this?

Thanks,
Gabe

 

Code:java

 
Random rnd = new Random();
 
//Random item from a list
list.get(rnd.nextInt(list.size()));
 
//Random item from an array
array[rnd.nextInt(array.length)];
 

Hope that's what you're looking for.

As a side note, don't save player objects, it causes memory leaks. Save their name or UUID and retrieve them from the server using that.

 

Jogy34 And how do you get player p?

 

...exactly like he said to.

 

Jogy34 Obviously I would store them in a list of strings.
List<String> players = new ArrayList<String>();
Also I will test.
Garris0n Exactly ^^

 

FabeGabeMC
Or you could do:

Code:java

Random random = new Random();
String player = list.remove(random.nextInt(list.size());

 

If you have a list of size 5, list.size() will return 5, which will cause the Random object to return a number from 0 to 4, hence generating 5 numbers not 6.

 

Huh?

 

ZeusAllMighty11 So.... which one is right? ._. Just got back home

 

Getting a random value out of a list the way I showed works perfectly fine, I use it all the time. The only thing you have to worry about is if the array or list is of size 0. Then the nextInt() method will yell at you saying 'n must be positive'

 

nextInt() returns 0 inclusive, maximum exclusive. Passing "5" would return 0, 1, 2, 3, or 4.

 

Oops, sorry