How can I initialize a String array with length 0 in Java?

java arrays initialization
Ron Tuffin picture Ron Tuffin · Nov 3, 2009 · Viewed 311k times · Source

The Java Docs for the method
String[] java.io.File.list(FilenameFilter filter)
includes this in the returns description:

The array will be empty if the directory is empty or if no names were accepted by the filter.

How do I do a similar thing and initialize a String array (or any other array for that matter) to have a length 0?

Answer

Jon Skeet picture Jon Skeet · Nov 3, 2009

As others have said,

new String[0]

will indeed create an empty array. However, there's one nice thing about arrays - their size can't change, so you can always use the same empty array reference. So in your code, you can use:

private static final String[] EMPTY_ARRAY = new String[0];

and then just return EMPTY_ARRAY each time you need it - there's no need to create a new object each time.

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