How to use java BigDecimal

import java.math.BigDecimal;

public class DecimalTester {
  public static void main(String args[]) {
      BigDecimal value = new BigDecimal("0");
      value = value.setScale(2, BigDecimal.ROUND_HALF_UP);
      String ValueWithDouble = String.valueOf(value);
      System.out.println("Tax : " + ValueWithDouble);
      System.out.println("Tax : " + value.doubleValue());
  }
}