Java lang.Long.reverse() method in Java with Examples
Last Updated :
23 May, 2019
java.lang.Long.reverse() is a built-in function in Java which returns the value obtained by reversing the order of the bits in the two's complement binary representation of the specified long value.
Syntax:
public static long reverse(long num)
Parameter :
num - the number passed
Returns :
the value obtained by reversing the order of the bits in the
two's complement binary representation of the specified long value.
Examples:
Input : 254
Output : 9151314442816847872
Input : 8
Output : 1152921504606846976
The program below illustrates the java.lang.Long.reverse() function:
Program 1 :
CPP
// Java program that demonstrates the
// Long.reverse() function
// include lang package
import java.lang.*;
public class GFG {
public static void main(String[] args)
{
long l = 8;
System.out.println("The number after reversing bit= "
+ Long.reverse(l));
l = 254;
System.out.println("The number after reversing bit= "
+ Long.reverse(l));
}
}
Output:
The number after reversing bit= 1152921504606846976
The number after reversing bit= 9151314442816847872
Program 2 : When a negative number is passed
Java
// Java program that demonstrates the
// Long.reverse() function
// negative number
// include lang package
import java.lang.*;
public class GFG {
public static void main(String[] args)
{
long l = -8;
System.out.println("The number after reversing bit= "
+ Long.reverse(l));
l = -254;
System.out.println("The number after reversing bit= "
+ Long.reverse(l));
}
}
Output:
The number after reversing bit= 2305843009213693951
The number after reversing bit= 4683743612465315839
Program 3 : When a decimal number is passed
Java
// Java program that demonstrates the
// Long.reverse() function
// decimal number
// include lang package
import java.lang.*;
public class GFG {
public static void main(String[] args)
{
System.out.println("The number after reversing bit= "
+ Long.reverse(11.34));
}
}
Output:
prog.java:16: error: incompatible types: possible lossy conversion from double to long
+ Long.reverse(11.34));
Program 4 : When a string number is passed
Java
// Java program that demonstrates the
// Long.reverse() function
// string number
// include lang package
import java.lang.*;
public class GFG {
public static void main(String[] args)
{
System.out.println("The number after reversing bit= "
+ Long.reverse("12"));
}
}
Output:
prog.java:16: error: incompatible types: String cannot be converted to long
+ Long.reverse("12"));