两个数计算同比

import java.math.BigDecimal;

/**
 * @author liangyehui
 * @version v1.0
 * @create 2020/2/13
 **/
public class CompareTongbi {

    /**计算同比
     * @param preNum 同期数
     * @param sufNum 往期数
     */
    public static String percentBigDecimal(BigDecimal preNum, BigDecimal sufNum){
        double result = countDecimal(preNum,sufNum);
        if(result>0){
            return ""+result+"%";
        }
        if(result<0){
            return "-"+Math.abs(result)+"%";
        }
        if(result==0){
            return "0"+"%";
        }
        return null;
    }
    public static double countDecimal(BigDecimal preNum, BigDecimal sufNum){
        boolean preBoolean = verifyNum(preNum);
        boolean sufBoolean = verifyNum(sufNum);
        //同时为true计算
        if(preBoolean && sufBoolean){
            boolean b = verifyEqual(preNum, sufNum);
            if (b == false){
                return realCountDecimal(preNum,sufNum);
            }
            if (b){
                return 0;
            }
        }
        if(preBoolean == false && sufBoolean ==false){
            return 0;
        }
        if(sufBoolean ==false){
            return 100;
        }
        if(preBoolean ==false){
            return -100;
        }
        return  0;
    }
    //验证数字是否为零和null
    public static boolean verifyNum(BigDecimal num){
        if(null !=num && num.compareTo(BigDecimal.ZERO)!=0 ){
            return true;
        }
        return false;
    }

    //验证两个数字是否相等
    public static boolean verifyEqual(BigDecimal preNum, BigDecimal sufNum){
        int n = preNum.compareTo(sufNum);
        //比较 -1 小于   0 等于    1 大于
        if(n==0){
            return true;
        }
        return false;
    }
    //真正计算
    public static double realCountDecimal(BigDecimal preNum, BigDecimal sufNum){
        //(前面的数字-后面的数字)/后面的数字*100
        BigDecimal bigDecimal = (preNum.subtract(sufNum)).divide(sufNum,2,BigDecimal.ROUND_HALF_UP).multiply(new BigDecimal("100")).setScale(2, BigDecimal.ROUND_HALF_UP);
        if (bigDecimal.compareTo(BigDecimal.ZERO) !=0){
            return  bigDecimal.doubleValue();
        }
        return 0;
    }


}

来源：CSDN

作者：Gery_Liang

链接：https://blog.csdn.net/Gery_Liang/article/details/104796948