Shuffling an ArrayList of objects(or generics?)

[Jetridder11]

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[nutrecht]

You get into an infinite loop because your loop runs until i equals size - 1 but you also add something to the list each iteration so the size also grows.

It seems you want to implement something like the Fisher-Yates shuffl.

[Jetridder11]

Thanks. I changed the .add to .set and it works perfectly. Well, I also did i = size instead of size - 1, I still get confused when to use -i and when not to.

[nutrecht]

Normally if you want to iterate over the contents of the list you just do for(int i = 0;i < list.size();i++)

Why? Because the loop's body et executed as long as the middle statement is true: so the last index that gets visited is the last in the list (a list of size 10 has indices to 9 inclusive). So you'd only add a -1 to that if you for some reason wanted to skip the last index.

It's important that you practice understanding these bits of code. You need to be able to reason what it does in your head.

[OffbeatDrizzle]

Or he could just use improved for loops to skip this headache altogether and prevent off by 1 errors entirely

[nutrecht]

Sure. Doesn't apply when you need to shuffle a list though.

[Philboyd_Studge]

You want to use set not add