Integer To String Java

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Java int to String Conversion with examples

In this guide, we will learn how to convert an int to string in Java. We can convert int to String using String.valueOf() or Integer.toString() method. We can also use String.format() method for the conversion.

1. Convert int to String using String.valueOf()

String.valueOf(int i) method takes integer value as an argument and returns a string representing the int argument.

Method signature: public static String valueOf(int i)

parameters: i – integer that needs to be converted to a string

returns: A string representing the integer argument

Java – int to String using String.valueOf()

public class JavaExample {
    public static void main(String args[]) {
 	int ivar = 111;
 	String str = String.valueOf(ivar);
 	System.out.println("String is: "+str); 
 	//output is: 555111 because the str is a string 
 	//and the + would concatenate the 555 and str
 	System.out.println(555+str);
    }
 }

Output:

2. Convert int to String using Integer.toString()

Integer.toString(int i) method works same as String.valueOf(int i) method. It belongs to the Integer class and converts the specified integer value to String. for e.g. if passed value is 101 then the returned string value would be “101”.

Method signature: public static String toString(int i)

parameters: i – integer that requires conversion

returns: String representing the integer i.

Example:

int ivar2 = 200;
 String str2 = Integer.toString(ivar2);

Java – int to String using Integer.toString()

public class Example {
    public static void main(String args[]) {
         int ivar = 111;
 	String str = Integer.toString(ivar);
 	System.out.println("String is: "+str);
 	//output is: 555111 because the str is a string 
 	//and the + would concatenate the 555 and str
 	System.out.println(555+str);
 	   
 	//output is: 666 because ivar is int value and the
         //+ would perform the addition of 555 and ivar
 	System.out.println(555+ivar);
    }
 }

Output:

String is: 111
 555111
 666

Example: Converting int to String

This program demonstrates the use of both the above mentioned methods(String.valueOf() and Integer.toString()). Here we have two integer variables and we are converting one of them using String.valueOf(int i) method and other one using Integer.toString(int i) method.

public class IntToString {
     public static void main(String[] args) {
         
         /* Method 1: using valueOf() method
          * of String class.
          */
         int ivar = 111;
         String str = String.valueOf(ivar);
         System.out.println("String is: "+str);
         
         /* Method 2: using toString() method 
          * of Integer class
          */
         int ivar2 = 200;
         String str2 = Integer.toString(ivar2);
         System.out.println("String2 is: "+str2);
     }
 }

Output:

String is: 111
 String2 is: 200

3. String.format() method for conversion

public class JavaExample{  
    public static void main(String args[]){  
 	int num = 99;  
 	String str = String.format("%d",num);  
 	System.out.println("hello"+str);  
    }
 }

Output: