Java String isEmpty() method with example

Java.lang.String.isEmpty() String method checks whether a String is empty or not. This method returns true if the given string is empty, else it returns false. The isEmpty() method of the String class is included in Java string since JDK 1.6. In other words, you can say that this method returns true if the length of the string is 0. 

Syntax of Java String isEmpty()

public boolean isEmpty();

Return Value

• It returns true if the string length is 0.
• Returns false otherwise.

Example

Input String1 : Hello_Gfg
Input String2 :
Output for String1 : false
Output for String2 : true

Examples of String isEmpty() method

Example 1:

Java program to illustrate the working of isempty().

Java

// Java program to demonstrate working of
// isEmpty() method
class Gfg {
    public static void main(String args[])
    {
        // non-empty string
        String str1 = "Hello_Gfg";

        // empty string
        String str2 = "";

        // prints false
        System.out.println(str1.isEmpty());

        // prints true
        System.out.println(str2.isEmpty());
    }
}

Output

false
true

Example 2:

A Java Program to show that an empty string is different from a blank String.

Java

// Java Program to demonstrate
// String isEmpty() method
import java.io.*;

class GFG {
    public static void main(String[] args)
    {
        String s1 = " ";
        String s2 = " Geek ";
        String s3 = "";

        System.out.println(s1.isEmpty());
        System.out.println(s2.isEmpty());
        System.out.println(s3.isEmpty());
    }
}

Output

false
false
true

FAQ on Java String isEmpty()

Q1. Are Empty String and Null Strings the same?

Ans:

No, Empty Strings and Null Strings are not the same. Empty String supports isEmpty() whereas Null strings do not support isEmpty() method in Java. 

Example:

String s1="";
String s2=null;

Program to demonstrate the difference between them:

Java

// Java Program to check if
// Empty String and Null String
// are equal
import java.io.*;

// Driver Class
class GFG {
    // main function
    public static void main(String[] args)
    {
        String s1 = "";
        String s2 = null;

        // Chacking if Empty String is same as
        // Null String
        if (s1 == s2) {
            System.out.println("Equal");
        }
        else {
            System.out.println("Not Equal");
        }
    }
}

Output

Not Equal

Q2. What is Blank String?

Ans:

Blank Strings are strings that contain only white spaces. isEmpty() method in itself is not sufficient but if used with trim() method can tell if the string is empty or not.

Example:

Java

// Java Program to demonstrate
// Blank String
import java.io.*;

// Driver Class
class GFG {
    // main function
    public static void main(String[] args)
    {
        String s1 = " ";

        if (s1.isEmpty())
            System.out.println("It is Empty");
        else
            System.out.println("Not Empty");

        if (s1.trim().isEmpty())
            System.out.println("Using trim(): It is Empty");
        else
            System.out.println("Not Empty");
    }
}

Output

Not Empty
Using trim(): It is Empty