Removing an element from an Array (Java) [duplicate]

Answer 1

Nice looking solution would be to use a List instead of array in the first place.

List.remove(index)

If you have to use arrays, two calls to System.arraycopy will most likely be the fastest.

Foo[] result = new Foo[source.length - 1];
System.arraycopy(source, 0, result, 0, index);
if (source.length != index) {
    System.arraycopy(source, index + 1, result, index, source.length - index - 1);
}

(Arrays.asList is also a good candidate for working with arrays, but it doesn't seem to support remove.)

Answer 2

Some more pre-conditions are needed for the ones written by Bill K and dadinn

Object[] newArray = new Object[src.length - 1];
if (i > 0){
    System.arraycopy(src, 0, newArray, 0, i);
}

if (newArray.length > i){
    System.arraycopy(src, i + 1, newArray, i, newArray.length - i);
}

return newArray;

Answer 3

Copy your original array into another array, without the element to be removed.

A simplier way to do that is to use a List, Set... and use the remove() method.

Answer 4

okay, thx a lot now i use sth like this:

public static String[] removeElements(String[] input, String deleteMe) {
    if (input != null) {
        List<String> list = new ArrayList<String>(Arrays.asList(input));
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).equals(deleteMe)) {
                list.remove(i);
            }
        }
        return list.toArray(new String[0]);
    } else {
        return new String[0];
    }
}

Answer 5

Swap the item to be removed with the last item, if resizing the array down is not an interest.

Answer 6

You can't remove an element from the basic Java array. Take a look at various Collections and ArrayList instead.