Four operations (Double type number) tool class

-

-Addition, subtraction, multiplication, division, and rounding operations of double type data

- Note: The current division operation is inaccurate to keep the decimal place, sorry.

You can use the split method of String to handle it yourself.

-

ArithmeticDouble.java

package com.my.test;

import java.math.BigDecimal;

/**
 * Description: 四则运算(Double类型数)
 * Copyright  : Copyright (c) 2016
 * Email      : [email protected]
 * Author     : Jusenr
 * Date       : 2016/7/26 19:36
 */
public class ArithmeticDouble {
    
    
    /**
     * Double数四舍五入
     *
     * @param v     double型数据
     * @param scale 精确度
     * @return Double
     */
    public static double round(double v, int scale) {
        if (scale < 0) {
            throw new IllegalArgumentException(
                    "The scale must be a positive integer or zero");
        }
        BigDecimal b = new BigDecimal(Double.toString(v));
        BigDecimal one = new BigDecimal("1");
        return b.divide(one, scale, BigDecimal.ROUND_HALF_UP).doubleValue();
    }

    /**
     * 两个Double数相加
     *
     * @param v1 double型数据
     * @param v2 double型数据
     * @return Double
     */
    public static Double add(Double v1, Double v2) {
        BigDecimal b1 = new BigDecimal(v1.toString());
        BigDecimal b2 = new BigDecimal(v2.toString());
        return b1.add(b2).doubleValue();
    }

    /**
     * 两个Double数相减
     *
     * @param v1 double型数据
     * @param v2 double型数据
     * @return Double
     */
    public static Double sub(Double v1, Double v2) {
        BigDecimal b1 = new BigDecimal(v1.toString());
        BigDecimal b2 = new BigDecimal(v2.toString());
        return b1.subtract(b2).doubleValue();
    }


    /**
     * 两个Double数相乘
     *
     * @param v1 double型数据
     * @param v2 double型数据
     * @return Double
     */
    public static Double mul(Double v1, Double v2) {
        BigDecimal b1 = new BigDecimal(v1.toString());
        BigDecimal b2 = new BigDecimal(v2.toString());
        return b1.multiply(b2).doubleValue();
    }


    /**
     * 两个Double数相除，并保留scale位小数
     *
     * @param v1    double型数据
     * @param v2    double型数据
     * @param scale 精确度
     * @return Double
     */
    public static Double div(Double v1, Double v2, int scale) {
        if (scale < 0) {
            throw new IllegalArgumentException(
                    "The scale must be a positive integer or zero");
        }
        BigDecimal b1 = new BigDecimal(v1.toString());
        BigDecimal b2 = new BigDecimal(v2.toString());
        return b1.divide(b2, scale, BigDecimal.ROUND_HALF_UP).doubleValue();
    }
}