Java.math.BigInteger.testBit() Method



The java.math.BigInteger.testBit(int n) returns true if and only if the designated bit is set. It computes (this & (1<<n)) != 0).


Following is the declaration for java.math.BigInteger.testBit() method

public boolean testBit(int n)


  • n - index of bit to test

Return Value

This method returns true if and only if the designated bit of this BigInteger is set.


  • ArithmeticException - n is negative


The following example shows the usage of math.BigInteger.testBit() method

package com.tutorialspoint;

import java.math.*;

public class BigIntegerDemo {

public static void main(String[] args) {

	// create a BigInteger object
	BigInteger bi;

	// create 2 boolean objects
	Boolean b1, b2;

	bi = new BigInteger("10"); 

	// perform testbit on bi at index 2 and 3
	b1 = bi.testBit(2);
	b2 = bi.testBit(3);

	String str1 = "Test Bit on " + bi + " at index 2 returns " +b1;
	String str2 = "Test Bit on " + bi + " at index 3 returns " +b2;

	// print b1, b2 values
	System.out.println( str1 );
	System.out.println( str2 );

Let us compile and run the above program, this will produce the following result:

Test Bit on 10 at index 2 returns false
Test Bit on 10 at index 3 returns true