import java.math.BigDecimal;
import java.math.RoundingMode;
import java.text.DecimalFormat;
class Decimal{
public static void controlFormatTwo(double value , int length){
BigDecimal bd = new BigDecimal(value);
bd = bd.setScale(length, BigDecimal.ROUND_FLOOR);
double r = bd.doubleValue();
System.out.println(r);
}
public static void controlFormat(double value , String patern){
DecimalFormat df = new DecimalFormat(patern);
df.setRoundingMode(RoundingMode.FLOOR);
String str = df.format(value);
System.out.println(str);
}
public static void main (String[] args ){
controlFormatTwo(Math.PI, 9);
controlFormat(Math.PI, "#.#########");
}
}
