Useful method from Apache Commons:

 org.apache.commons.lang.StringUtils.isBlank(String str)

https://commons.apache.org/proper/commons-lang/javadocs/api-2.6/org/apache/commons/lang/StringUtils.html#isBlank(java.lang.String)

Answer from puczo on Stack Overflow
🌐
W3Schools
w3schools.com › java › ref_string_isempty.asp
Java String isEmpty() Method
The isEmpty() method checks whether a string is empty or not. This method returns true if the string is empty (length() is 0), and false if not. ... If you want to use W3Schools services as an educational institution, team or enterprise, send ...
Discussions

In Java, should I use (String ) isEmpty() or isBlank() when checking an XML object for an empty value?
What behavior do you want if the xml parser emits " " as the config value? More on reddit.com
🌐 r/AskProgramming
4
1
September 26, 2022
Question about .isEmpty() and .contains("")
isEmpty() checks for string length and returns true if it's zero, while contains("") will return true unless the string isn't initialized/null. For checking empty strings or strings containing only whitespace you could also use the method isBlank(). Hope this helps! More on reddit.com
🌐 r/learnjava
7
5
July 25, 2023
New Methods on Java Strings With JDK 11
Maybe one day they will even add string padding utils to the stdlib. More on reddit.com
🌐 r/java
74
110
May 3, 2018
!isEmpty vs != “”
IIRC isEmpty checks a 1 bit flag on the collection, whereas at the very minimum checking against “” instantiates a string to compare against on the heap, which is comparatively astronomically expensive More on reddit.com
🌐 r/swift
26
10
January 5, 2024
🌐
Oracle
docs.oracle.com › javase › 8 › docs › api › java › lang › String.html
String (Java Platform SE 8 )
October 20, 2025 - List<String> strings = new LinkedList<>(); strings.add("Java");strings.add("is"); strings.add("cool"); String message = String.join(" ", strings); //message returned is: "Java is cool" Set<String> strings = new LinkedHashSet<>(); strings.add("Java"); strings.add("is"); strings.add("very"); strings.add("cool"); String message = String.join("-", strings); //message returned is: "Java-is-very-cool" Note that if an individual element is null, then "null" is added. ... delimiter - a sequence of characters that is used to separate each of the elements in the resulting String
🌐
GeeksforGeeks
geeksforgeeks.org › java › java-string-isempty-method-example
Java String isEmpty() Method with Example - GeeksforGeeks
November 20, 2024 - In Java, the String isEmpty() method checks if a string is empty (length is zero). This method returns true if the string is empty and false otherwise.
🌐
Medium
medium.com › @AlexanderObregon › java-string-isempty-method-explained-a731faf082aa
Java String isEmpty() Method Guide | Medium
June 23, 2024 - The isEmpty() method is part of the String class in Java, which is fundamental for handling and manipulating strings. This method provides a simple way to check whether a string is empty, meaning it contains no characters.
🌐
Baeldung
baeldung.com › home › java › java string › checking for empty or blank strings in java
Checking for Empty or Blank Strings in Java | Baeldung
January 8, 2024 - The most convenient way is to use Apache Commons Lang, which provides helpers such as StringUtils.isBlank. If we want to stick to plain Java, we can use a combination of String#trim with either String#isEmpty or String#length.
Find elsewhere
🌐
Vultr Docs
docs.vultr.com › java › standard-library › java › lang › String › isEmpty
Java String isEmpty() - Check If Empty | Vultr Docs
December 17, 2024 - The isEmpty() method in Java is a straightforward and efficient way for checking whether a given string has a length of zero, which means it is an empty string. This method is part of the String class in Java's standard library, making it readily ...
🌐
Reddit
reddit.com › r/askprogramming › in java, should i use (string ) isempty() or isblank() when checking an xml object for an empty value?
r/AskProgramming on Reddit: In Java, should I use (String ) isEmpty() or isBlank() when checking an XML object for an empty value?
September 26, 2022 -

I have some config file and it is deployed in many regions. Some regions have certain requirements for example lets say one region needed a username and password (basic auth). The current setup is that each deployment has it's own config file and only the instances where it is needed are these values included in the respective config.xml file.

So I have in my Java code some logic that says

'if this element is in the XML, set the corresponding variable with its value, if not do nothing'

So when I'm trying to see if that value is present or if the tag is empty/blank, which String utility should I use to check?

example code (default option left open as empty string):

if (my_config.getString(USER_ID_ELEMENT, "") != null
    & my_config.getString(PASSWORD_ELEMENT, "") != null) {
		my_userId = m_config.getString(USER_ID_ELEMENT, "");
		my_password = m_config.getString(PASSWORD_ELEMENT, "");

Here I'm checking if it is not null, but I don't think it's a very good test since I don't know if an empty XML tag is blank or is empty (i think null isn't even an option)?

🌐
TechVidvan
techvidvan.com › tutorials › java-string-isempty-method
Java String isEmpty() Method with Examples - TechVidvan
July 8, 2024 - Java isEmpty() method is a powerful tool that allows developers to efficiently check if a string is empty or null, simplifying the process of handling strings in programming.
🌐
Programiz
programiz.com › java-programming › library › string › isempty
Java String isEmpty()
class Main { public static void main(String[] args) { String str1 = "Java Programming"; String str2 = ""; System.out.println(str1.isEmpty()); // false System.out.println(str2.isEmpty()); // true } }
🌐
Scaler
scaler.com › home › topics › isempty() in java
Java String isEmpty - Scaler Topics
January 4, 2024 - ... The First string i.e "Scaler" ... The String class of java has the isEmpty() method that is used to check whether the given string is empty or not....
🌐
Codecademy
codecademy.com › docs › java › strings › .isempty()
Java | Strings | .isEmpty() | Codecademy
March 4, 2023 - The .isEmpty() method returns true if a string has no content. It returns false if the string has content. ... Looking for an introduction to the theory behind programming? Master Python while learning data structures, algorithms, and more!
🌐
Coderanch
coderanch.com › t › 203109 › java › Efficient-Check-Empty-String
Efficient Way to Check Empty String (Performance forum at Coderanch)
We use (string != null || string.trim().length() == 0) to check if string is empty. Calling a method which actually iterate through string and checks for non-whitespace character .
🌐
Baeldung
baeldung.com › home › java › java string › difference between string isempty() and isblank()
Difference Between String isEmpty() and isBlank() | Baeldung
December 2, 2025 - The above table summarizes that if the String doesn’t contain any character, both methods return true. Additionally, the escape sequences \t, \n, \r, \f, and \s are considered whitespace characters, so only isBlank() returns true. In contrast, isEmpty() returns false for all of them. Finally, for any other character different from the ones shown in the table, both methods return false. Before Java 11, developers typically used the combination of String.trim() and String.isEmpty() to validate that a text contains only whitespace characters.
🌐
Reddit
reddit.com › r/learnjava › question about .isempty() and .contains("")
r/learnjava on Reddit: Question about .isEmpty() and .contains("")
July 25, 2023 -

SORRY

I JUST REALISED I MADE A MISTAKE I WANTED TO ASK ABOUT EQUALS("") BUT AT THE SAME TIME I WAS FIGHTING WITH ANOTHER EXCERCISE IN WHICH I HAD TO USE CONTAINS() METHOD AND THIS MESSED UP MY THOUGHTS SORRY FOR WASTING YOUR TIME :/

but still i was able to get some usefull info about contains method so it wasn't as much wasted effort but still sorry

Hi i'm doing(or atleast trying to do) mooc.fi java part 1 course and there in some exercises is required to check for empty input.

So there is my question what is difference between .isEmpty() and .Equals("") because i like to use the first one but in suggested solutions always is used ".Equals("") and i'm wondering is there any rule for using .isEmpty(), maybe it's the matter of optimalization etc. or maybe both are as good

I know it can be stupid question but it's better to ask that and get rid of bad habits in writing code as soon as possible :D

In advance thanks for answers

P.S i hope everything is easy to understand unfortunately my english is still far from good :D

Top answer
1 of 5
2
isEmpty() checks for string length and returns true if it's zero, while contains("") will return true unless the string isn't initialized/null. For checking empty strings or strings containing only whitespace you could also use the method isBlank(). Hope this helps!
2 of 5
1
Please ensure that: Your code is properly formatted as code block - see the sidebar (About on mobile) for instructions You include any and all error messages in full - best also formatted as code block You ask clear questions You demonstrate effort in solving your question/problem - plain posting your assignments is forbidden (and such posts will be removed) as is asking for or giving solutions. If any of the above points is not met, your post can and will be removed without further warning. Code is to be formatted as code block (old reddit/markdown editor: empty line before the code, each code line indented by 4 spaces, new reddit: https://i.imgur.com/EJ7tqek.png ) or linked via an external code hoster, like pastebin.com, github gist, github, bitbucket, gitlab, etc. Please, do not use triple backticks (```) as they will only render properly on new reddit, not on old reddit. Code blocks look like this: public class HelloWorld { public static void main(String[] args) { System.out.println("Hello World!"); } } You do not need to repost unless your post has been removed by a moderator. Just use the edit function of reddit to make sure your post complies with the above. If your post has remained in violation of these rules for a prolonged period of time (at least an hour), a moderator may remove it at their discretion. In this case, they will comment with an explanation on why it has been removed, and you will be required to resubmit the entire post following the proper procedures. To potential helpers Please, do not help if any of the above points are not met, rather report the post. We are trying to improve the quality of posts here. In helping people who can't be bothered to comply with the above points, you are doing the community a disservice. I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.
🌐
Oracle
docs.oracle.com › en › java › javase › 17 › docs › api › java.base › java › lang › String.html
String (Java SE 17 & JDK 17)
January 20, 2026 - The class String includes methods for examining individual characters of the sequence, for comparing strings, for searching strings, for extracting substrings, and for creating a copy of a string with all characters translated to uppercase or to lowercase. Case mapping is based on the Unicode Standard version specified by the Character class. The Java language provides special support for the string concatenation operator ( + ), and for conversion of other objects to strings.
🌐
Baeldung
baeldung.com › home › java › java string › java string.isempty()
Java.String.isEmpty() | Baeldung
April 11, 2025 - The method isEmpty() is a convenience method that checks if the size of a String is equal to zero.
🌐
JetBrains
jetbrains.com › help › inspectopedia › StringEqualsEmptyString.html
'String.equals()' can be replaced with 'String.isEmpty()' | Inspectopedia Documentation
December 3, 2025 - void checkString(String s){ if (s != null && s.isEmpty()) throw new IllegalArgumentException(); } By ID · Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings. StringEqualsEmptyString · Via Settings dialog · Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE. Settings or Preferences | Editor | Inspections | Java | Performance ·
🌐
Narkive
user.groovy.codehaus.narkive.com › WhPriVcp › groovy-string-isempty
[groovy-user] String isEmpty()
0 character strings are evaluated to true. Hi Guys, Is there a convenient way to test whether the String is null or "" ? In Java, I would use apache.commons.lang's StringUtils.isEmpty() I check the GDK and there isnt an .isEmpty() method. Any suggestions?