to generate random lottery no

i am new to java ,i wanted to make program to generate random lottery no using bigInteger

Code:

`import java.util.*;`

import java.Math.BigInteger;

class lottery

{

public static void main(String ar[])

{

Random r= new Random();

BigInteger b1=BigInteger.valueOf(100000000);

BigInteger b2=BigInteger.valueOf(r.nextInt(100000000));

BigInteger b=B1.add(B2);

System.out.println("your lottery no="+b);

}

}

after help of everyone code modefied to

Code:

`import java.util.*;`

import java.math.BigInteger;

class Lottery

{

public static void main(String ar[])

{

Random r= new Random();

int ch=0;

do

{

BigInteger b= new BigInteger(30,r);

BigInteger b1= BigInteger.valueOf(100000000);

if(b.compareTo(b1)>0)

{

System.out.println("your lottery no="+b);

ch=0;

}

else

{

System.out.println("try again");

ch=1;

}

}while(ch==1);

}