How to check whether empty or not every element of Varargs by recursive in Java?

Question

I have a problem it is not just passing Varargs to function, it is how to use Varargs in recursive function, I need generic function objects(List... args) send the n-1 element back to function until the last object by recursive and check these objects either null or empty. if all objects are both null and empty need to return false else true.

private boolean orObjects(List... args) {

    //all of the objects are null or empty
    if(args.length == 0)
    return false;

    //any of the objects is not null or not empty
    return true: orObjects(args.size(1,lenght)) //args.size(1,lenght) verbal 
}

Possible duplicate of [Passing a List in as varargs](https://stackoverflow.com/questions/12220324/passing-a-list-in-as-varargs) — D. Lawrence, Nov 28 '19 at 13:44
what is `return true: orObjects(args.size(1,lenght))` supposed to be? That does not even *resemble* compiling code. — luk2302, Nov 28 '19 at 13:44
https://stackoverflow.com/questions/12220324/passing-a-list-in-as-varargs it is only passing Varargs my point is the using Varargs as a parameter which is usable in Recursive function — Samet ÖZTOPRAK, Nov 28 '19 at 13:56

Joop Eggen · Answer 1 · 2019-11-28T13:50:49.527

2

private boolean orObjects(Xyz... args) {
    if (args.length == 0)
        return false;

    return orObjects(Arrays.copyOfRange(args, 1, args.length));
}

As args is just a Xyz[] you need to make a copy. Hence a List<Xyz> args would be better. Or a Stream<Xyz>.

edited Nov 28 '19 at 13:50

answered Nov 28 '19 at 13:45

Joop Eggen

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@Brother mistook copyOfRange end index with length - thanks – Joop Eggen Nov 28 '19 at 13:52

Ikbel · Answer 2 · 2021-04-10T22:40:19.353

1

   private boolean checkVarargsIsNotBlank(String... vararg) {
    if (vararg.length == 0)
        return true;
    return StringUtils.isNotBlank(vararg[0]) && checkIsNotBlank(Arrays.copyOfRange(vararg, 1, vararg.length));
}

edited Apr 10 '21 at 22:40

answered Apr 09 '21 at 07:18

Ikbel

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score 0 · Accepted Answer · answered Nov 28 '19 at 14:01

private boolean isNotEmptyOrNull(List list) {
    return list != null && !list.isEmpty() ? true : false;
}

private boolean orObjects(List... args) {

    if (args.length == 0)
        return false;

    return isNotEmptyOrNull(args[0]) ?
            true : orObjects(Arrays.copyOfRange(args, 1, args.length));

}

How to check whether empty or not every element of Varargs by recursive in Java?

3 Answers3