Java Program to Convert int to long
Last Updated :
10 Jan, 2023
Improve
Given a number of int datatype in Java, your task is to write a Java program to convert this given int datatype into a long datatype.
Example:
Input: intnum = 5 Output: longnum = 5 Input: intnum = 56 Output: longnum = 56
Int is a smaller data type than long. Int is a 32-bit integer while long is a 64-bit integer. They both are primitive data types and the usage depends on how large the number is.
Java int can be converted to long in two simple ways:
- Using a simple assignment. This is known as implicit type casting or type promotion, the compiler automatically converts smaller data types to larger data types.
- Using valueOf() method of the Long wrapper class in java which converts int to long.
- In this, we are simply assigning an integer data type to a long data type.
- Since integer is a smaller data type compared to long, the compiler automatically converts int to long, this is known as Implicit type casting or type promotion.
// Java program to demonstrate
// use of implicit type casting
import java.io.*;
import java.util.*;
class GFG {
public static void main(String[] args)
{
int intnum = 5;
// Implicit type casting , automatic
// type conversion by compiler
long longnum = intnum;
// printing the data-type of longnum
System.out.println(
"Converted type : "
+ ((Object)longnum).getClass().getName());
System.out.println("After converting into long:");
System.out.println(longnum);
}
}
// Java program to demonstrate// use of implicit type castingimport java.io.*;import java.util.*;class GFG { public static void main(String[] args) { int intnum = 5; // Implicit type casting , automatic // type conversion by compiler long longnum = intnum; // printing the data-type of longnum System.out.println( "Converted type : " + ((Object)longnum).getClass().getName()); System.out.println("After converting into long:"); System.out.println(longnum); }}Output
Converted type : java.lang.Long After converting into long: 5
- In this, we are converting int to long using the valueOf() method of the Long Wrapper class.
- The valueOf() method accepts an integer as an argument and returns a long value after the conversion.
// Java program to convert
// int to long using valueOf() method
import java.io.*;
class GFG {
public static void main(String[] args)
{
int intnum = 56;
Long longnum = Long.valueOf(intnum);
// printing the datatype to
// show longnum is of type
// long contains data of intnum
System.out.println(
"Converted type : "
+ ((Object)longnum).getClass().getName());
// accepts integer and
// returns a long value
System.out.println("After converting into long:"
+ "\n" + longnum);
}
}
// Java program to convert// int to long using valueOf() methodimport java.io.*;class GFG { public static void main(String[] args) { int intnum = 56; Long longnum = Long.valueOf(intnum); // printing the datatype to // show longnum is of type // long contains data of intnum System.out.println( "Converted type : " + ((Object)longnum).getClass().getName()); // accepts integer and // returns a long value System.out.println("After converting into long:" + "\n" + longnum); }}Output
Converted type : java.lang.Long After converting into long: 56
