I want to add a multidimensional Boolean Array to an ArrayList. How do I do that?
Below is an simple example:
public boolean[][] BooleanArray;
ArrayList<Boolean[][]> BooleanArrayList= new ArrayList<Boolean[][]>();
public void AddBooleanArrayToList(){
BooleanArrayList.add(BooleanArray);
}
However this example does not work. This error will prompt:
The method add(Boolean[][]) in the type ArrayList<Boolean[][]> is not applicable for the arguments (boolean[][])
The problem here is that you defined the ArrayList to take 2D arrays of the wrapper class Boolean, but you are trying to add a 2D array of the primitive type boolean. Those are not the same type, hence the error. You are able to get away with this when you aren't storing arrays thanks to a nice little Java feature called auto-boxing, which converts between Boolean and boolean automatically, but auto-boxing isn't smart enough to work on arrays. The fix is simple; just capitalize the B in "boolean" in the declaration for BooleanArray. It should look like so:
public Boolean[][] BooleanArray;
Alternatively, (not recommended) you could manually box your array when you want to add it to the ArrayList like so:
BooleanArrayList.add(
IntStream.range(0, BooleanArray.length)
.mapToObj((i) -> IntStream.range(0, BooleanArray[i].length)
.mapToObj((j) -> BooleanArray[i][j])
.toArray(Boolean[]::new))
.toArray(Boolean[][]::new));
