Kotlin: isNullOrEmpty vs TextUtils.isEmpty

Question

In Kotlin (Android project), which is preferable to use ?

isNullOrEmpty or TextUtils.isEmpty and why

I believe they do the exact thing and are "null" safe, right ?

They both check for `null` and a length of `0`, so they just do the same... I would then stick to Kotlin and use `CharSequence.isNullOrEmpty` — deHaar, Dec 13 '19 at 11:18

a_local_nobody · Accepted Answer · 2019-12-13T11:25:50.887

7

Based off of my question here

If your project will be ported to other frameworks, making use of isNullOrEmpty will probably result in a safer experience, because it's based on Kotlin (specifically package kotlin.text) and not on package android.text;

Why is this safer ?

Well, the implementation of isNullOrEmpty might change depending on the platform but it will be available to use and is part of Kotlin, compared to TextUtils.isEmpty being only for android.

edited Dec 13 '19 at 11:25

answered Dec 13 '19 at 11:20

a_local_nobody

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What other platform other than Android was OP referring to? – IgorGanapolsky Mar 15 '20 at 18:09
@IgorGanapolsky with Kotlin Native being a thing (no expert on this) i believe that you can write Kotlin code which could be converted to ios or to android, if that answers your comment ? – a_local_nobody Mar 15 '20 at 18:11
Interesting, haven't heard of anybody developing Kotlin Native in production at this point. – IgorGanapolsky Mar 15 '20 at 18:14
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me neither @IgorGanapolsky, this question was just related to something i found myself while coding normal android :) – a_local_nobody Mar 15 '20 at 18:24

score 3 · Answer 2 · answered Dec 13 '19 at 11:21

3

I would say isNullOrEmpty is slightly preferable, because it's a language's feature. TextUtils.isEmpty is a library function, external to Kotlin.

answered Dec 13 '19 at 11:21

Anton Malyshev

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score 1 · Answer 3 · answered Dec 13 '19 at 11:18

1

For string.isEmpty(), a null string value will throw a NullPointerException Incase of isNullOrEmpty it will check first value is null or not and it will proceed for the empty check. isNullOrEmpty is preferable

answered Dec 13 '19 at 11:18

Shanmuka Chowdary

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What about `TextUtils.isEmpty`, which was mentioned in the question? The question did not mention `String.isEmpty` – deHaar Dec 13 '19 at 11:19
Both will be the same, The only difference is we are taking the advantage of kotlin extensions here in kotlin – Shanmuka Chowdary Dec 13 '19 at 11:24

score 1 · Answer 4 · answered Dec 13 '19 at 11:23

The code for TextUtils.isEmpty:

public static boolean isEmpty(@Nullable CharSequence str) {
        return str == null || str.length() == 0;
    }

The code for isNullOrEmpty:

public inline fun CharSequence?.isNullOrEmpty(): Boolean {
    contract {
        returns(false) implies (this@isNullOrEmpty != null)
    }

    return this == null || this.length == 0
}

Witch is basically the same, the inline function also has a contract that will tell the compiler to return false if the value is not null, not sure what the actual usage is, maybe it's an optimization.

score 1 · Answer 5 · answered Dec 13 '19 at 11:27

Yes , the only difference is NullPointerException.

In isNullOrEmpty first it will check string is null or not .if it is not null then it will check it is check string is empty or not . If any of the condition will true then method will return true.

In TextUtils.isEmpty it check string is empty or not .If string is null then it will throw NullPointerException and your app will crash .

Sergey Emeliyanov · Answer 6 · 2019-12-13T13:48:59.680

TextUtils.isEmpty is basically the same thing with isNullOrEmpty(). Yet, there are differences in terms of availability and compilation:

1) TextUtils.isEmpty is available from the android.text package, available with Android SDK, and isNullOrEmpty() requires Koltin dependency (kotlin.text package).

2) Another difference is that isNullOrEmpty() is an inline extension function and it is compiled differently, perhaps with a slight performance boost.

Apart from these, there is another useful inline function isNullOrBlank(). It also returns true if the String contains only white spaces.

score 0 · Answer 7 · answered Dec 13 '19 at 11:23

0

In Kotlin isNullOrEmpty is preferable. TextUtils.isEmpty is specific to Java. Both returns boolean if string is empty or null.

answered Dec 13 '19 at 11:23

Prashant Sable

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Are there exceptions thrown? – IgorGanapolsky Mar 15 '20 at 18:17

Kotlin: isNullOrEmpty vs TextUtils.isEmpty

7 Answers7