Learn to use String.isBlank() method to determine if a given string is blank or empty or contains only white spaces. The isBlank() method has been added in Java 11.
To check if a given string does not have even blank spaces, use String.isEmpty()
method.
1. String isBlank() API
- It returns
true
if the given string is empty or contains only white space code points, otherwisefalse
. - It uses Character.isWhitespace(char) method to determine a white space character.
/**
* returns - true if the string is empty or contains only white space codepoints
* - otherwise false
*/
public boolean isBlank()
2. String isBlank() Example
Java program to check if a given string is blank or not.
"ABC".isBlank() //false " ABC ".isBlank() //false " ".isBlank() //true "".isBlank() ) //true
3. Difference between isBlank() and isEmpty()
Both methods are used to check for blank or empty strings in java. The difference between both methods is that:
- isEmpty() method returns true if, and only if, the string length is 0.
- isBlank() method only checks for non-whitespace characters. It does not check the string length.
In other words, a String with only white space characters is blank but not empty.
"ABC".isBlank() //false " ".isBlank() //true "ABC".isEmpty() //false " ".isEmpty() //false
Happy Learning !!