import java.math.*;
class Main{
   public static void main(String[] args) {

      // create 3 BigDecimal objects
      BigDecimal bg1, bg2, bg3;
      MathContext mc=new MathContext(10,RoundingMode.DOWN);

      bg1 = new BigDecimal("2.4",mc);
      bg2 = new BigDecimal("32301",mc);

      bg3 = bg1.divide(bg2,mc); // divide bg1 with bg2

      String str = "Division result is " +bg3;

      // print bg3 value
      System.out.println( str );
   }
}

giving wrong answer

You need to first check what is the nature of the result of the division. If it is a price, then set the scale to 2 beforehand. If it is a rate (e.g. an exchange rate, an interest rate, etc.) then choose a suitable scale to make your calculations sufficiently precise, and then you can call stripTrailingZeros if you like to make the presentation nicer:

BigDecimal.valueOf(1).divide(BigDecimal.valueOf(3), 8, RoundingMode.HALF_EVEN)
    ➛ 0.33333333
BigDecimal.valueOf(1).divide(BigDecimal.valueOf(4), 8, RoundingMode.HALF_EVEN)
    ➛ 0.25000000
BigDecimal.valueOf(1).divide(BigDecimal.valueOf(4), 8, RoundingMode.HALF_EVEN)
        .stripTrailingZeros()
    ➛ 0.25

However, if you are changing the scale purely for presentational reasons, I would prefer to leave the scale at a constant 2 for prices and 8 (or higher) for rates, and then use suitable formatting to suppress trailing zeros when you eventually come to printing out the values:

new DecimalFormat("#.##########").format(new BigDecimal("12.340000000"))
    ➛ "12.34"

You should write the code as follows:

int temp = BigDecimal.valueOf(v1.longValue())
        .divide(BigDecimal.valueOf(constant1)).intValue();

The thing about BigDecimal and BigInteger is that they mostly operate with instances of these classes and not with primitive types. Results of operations are also new instances of these classes.

One other remark: I advise to use valueOf static method instead of a constructor, because by doing this you may have a possibility to avoid creation of new objects. Using a constructor makes creation of a new object explicit, which is not necessary in this case at all.