怎样实现四舍五入，保留小数点后两位小数？

package com.venus.csdn;

import java.text.NumberFormat;

public class Number {



public static void main(String[] args){

double numb = 100000.006;

NumberFormat nf = NumberFormat.getNumberInstance();

System.out.println("nf : " + nf);

nf.setMaximumFractionDigits(2);

nf.setMinimumFractionDigits(2);

System.out.println(nf.format(numb));

}

}