How To Randomly Assign Specific Values In Array Or ArrayList

I'm trying to build a monopoly like game, and atm I'm trying to find way how to build the Community and Chance chest cards. so far, my logic is

1-create an ArrayList of cards with a given order

2-for a given number of times(for loop) generate 2 random numbers ,which will be the parameters for Collection.swap().

3-swap.

here's the code for the shuffler Button

shuffler.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
for(int i=0;i<shuffeledMessages.length;i++){
int randoma=(int)(Math.random()*4);
int randomb=(int)(Math.random()*4);
Collections.swap(myMessages,randoma,randomb);
}
}
});

For now things seem to work pretty ok, but I'm wondering if this is a good and efficient way to shuffle a card chest especially in case of large number of cards. plus, I'm not sure what would be a good loop count for effective shuffling, in my case I used i<arraylist.size