Java tutorial
import java.math.BigDecimal; /* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * * */ public class Main { /** * Round the given value to the specified number of decimal places. The * value is rounded using the {@link BigDecimal#ROUND_HALF_UP} method. * * @param x the value to round. * @param scale the number of digits to the right of the decimal point. * @return the rounded value. * @since 1.1 */ public static double round(double x, int scale) { return round(x, scale, BigDecimal.ROUND_HALF_UP); } /** * Round the given value to the specified number of decimal places. The * value is rounded using the given method which is any method defined in * {@link BigDecimal}. * * @param x the value to round. * @param scale the number of digits to the right of the decimal point. * @param roundingMethod the rounding method as defined in * {@link BigDecimal}. * @return the rounded value. * @since 1.1 */ public static double round(double x, int scale, int roundingMethod) { try { return (new BigDecimal(Double.toString(x)).setScale(scale, roundingMethod)).doubleValue(); } catch (NumberFormatException ex) { if (Double.isInfinite(x)) { return x; } else { return Double.NaN; } } } }