Here you can find the source of round(double d, int decimalPlace)
public static double round(double d, int decimalPlace)
//package com.java2s; /**/*from ww w . jav a2 s .c o m*/ * SOWGware, Copyright 2010 * * This file is part of SOWGcalc. SOWGcalc is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. SOWGcalc is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with SOWGcalc. If not, see <http://www.gnu.org/licenses/>. */ import java.math.BigDecimal; public class Main { public static double round(double d, int decimalPlace) { try { BigDecimal bd = new BigDecimal(Double.toString(d)); bd = bd.setScale(decimalPlace, BigDecimal.ROUND_HALF_UP); return bd.doubleValue(); } catch (NumberFormatException e) { //on NaN or +/- infinity return the value return d; } } }