Java – isBlank() vs isEmpty() method of String class

By Atul Rai | Last Updated: June 18, 2022 Previous Next

In this short article, you will get to know about the difference between the isBlank() and isEmpty() methods of the String class in Java.

isBlank()	isEmpty()
Added in the JDK 11 release.	Added in the JDK 1.6 release.
Returns `true` if a string is empty or only contains white space otherwise returns `false`.	Returns `true` if the length of the string is 0, otherwise returns `false`.
It uses `Character.isWhitespace(int)` method to determine a white space character.	It uses the `length()` method to determine the emptiness of a string.

Checkout the Java 11- New Methods of String Class

Let’s have a look at the below examples.

#test case 1

final String str1 = "";

System.out.println(str1.isBlank()); // return --> true
System.out.println(str1.isEmpty()); // return --> true

#test case 2

final String str2 = "  ";

System.out.println(str2.isBlank()); // return --> true
System.out.println(str2.isEmpty()); // return --> false

#test case 3

final String str3 = "\u2005";

System.out.println(str3.isBlank()); // return --> true
System.out.println(str3.isEmpty()); // return --> false

#test case 4

final String str4 = "  ";

System.out.println(str4.isBlank()); // return --> true
System.out.println(str4.trim().isEmpty()); // return --> true

#test case 5

final String str5 = "\u2005";

System.out.println(str5.isBlank()); // return --> true
System.out.println(str5.trim().isEmpty()); // return --> false

Note: trim() is not aware of Unicode whitespace characters and hence does not consider ‘\u2005′ a whitespace character.

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