How do I remove objects from an array in Java?

Question

Given an array of n Objects, let\'s say it is an array of strings, and it has the following values:

foo[0] = \"a\";
foo[1]          


        

Answer 1

EDIT:

The point with the nulls in the array has been cleared. Sorry for my comments.

Original:

Ehm... the line

array = list.toArray(array);

replaces all gaps in the array where the removed element has been with null. This might be dangerous, because the elements are removed, but the length of the array remains the same!

If you want to avoid this, use a new Array as parameter for toArray(). If you don`t want to use removeAll, a Set would be an alternative:

        String[] array = new String[] { "a", "bc" ,"dc" ,"a", "ef" };

        System.out.println(Arrays.toString(array));

        Set<String> asSet = new HashSet<String>(Arrays.asList(array));
        asSet.remove("a");
        array = asSet.toArray(new String[] {});

        System.out.println(Arrays.toString(array));

Gives:

[a, bc, dc, a, ef]
[dc, ef, bc]

Where as the current accepted answer from Chris Yester Young outputs:

[a, bc, dc, a, ef]
[bc, dc, ef, null, ef]

with the code

    String[] array = new String[] { "a", "bc" ,"dc" ,"a", "ef" };

    System.out.println(Arrays.toString(array));

    List<String> list = new ArrayList<String>(Arrays.asList(array));
    list.removeAll(Arrays.asList("a"));
    array = list.toArray(array);        

    System.out.println(Arrays.toString(array));

without any null values left behind.

Answer 2

An alternative in Java 8:

String[] filteredArray = Arrays.stream(array)
    .filter(e -> !e.equals(foo)).toArray(String[]::new);