Integer toOctalString() Method in Java (original) (raw)

Last Updated : 19 Oct, 2021

Octal is the base-8 number system and uses the digits 0 to 7 in operation. Octal is widely used in computing on systems like the PDP-8, and IBM mainframes employed 12-bit, 24-bit or 36-bit words.
The Java.lang.Integer.toOctalString() method is a built-in function in Java that is used to return a string representation of the integer argument as an unsigned integer in base 8.
Syntax:

public static String toOctalString(int num)

Parameters : The method accepts a single parameter num of integer type which is required to be converted to a string.
Return Value: The function returns a string representation of the integer argument as an unsigned integer in base 8.
Examples:

Consider an integer a = 86 Octal output = 126

Consider an integer a = 186 Octal output = 272

Below programs illustrate the working of Integer.toOctalString() method:
Program 1: For positive integer:

Java

import java.lang.*;

public class Geeks {

`` public static void main(String[] args)

`` {

`` int a = 527 ;

`` System.out.println( "Integral Number = " + a);

`` System.out.println( "Octal Number = " + Integer.toOctalString(a));

`` }

}

Output:

Integral Number = 527 Octal Number = 1017

Program 2: For Negative integer:

Java

import java.lang.*;

public class Geeks {

`` public static void main(String[] args)

`` {

`` int a = - 51 ;

`` System.out.println( "Integral Number = " + a);

`` System.out.println( "Octal Number = " + Integer.toOctalString(a));

`` }

}

Output:

Integral Number = -51 Octal Number = 37777777715

Program 3: For decimal value or a string:
Note: Whenever a decimal number or a string is passed as an argument, it returns an error message which results incompatible types.

Java

import java.lang.*;

public class Geeks {

`` public static void main(String[] args)

`` {

`` double a = 18.71 ;

`` System.out.println( "Octal output = " + Integer.toOctalString(a));

`` String b = "63" ;

`` System.out.println( "Octal output = " + Integer.toOctalString(a));

`` }

}

Output:

prog.java:15: error: incompatible types: possible lossy conversion from double to int System.out.println("Octal output = " + Integer.toOctalString(a)); ^ prog.java:21: error: incompatible types: possible lossy conversion from double to int System.out.println("Octal output = " + Integer.toOctalString(a)); ^ Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output 2 errors