Java的大数操作分为BigInteger和BigDecimal

Java的大数操作分为BigInteger和BigDecimal,但这两给类是分开使用的,有时候在编程的时候显得略微繁琐,现在编写了一个将二者合二为一的大数操作类。

大数操作类代码如下:

 

复制代码
  1 package blog;
  2 
  3 import java.math.BigDecimal;
  4 import java.math.BigInteger;
  5 import java.math.RoundingMode;
  6 
  7 /**
  8  * 
  9  * @author 瓦尔登湖畔的小木屋
 10  * BigNumberOperation封装了对十进制大数整数和大数浮点数的四则运算的操作
 11  */
 12 public class BigNumberOperation {
 13     /**
 14      * 对加法的封装操作
 15      */
 16     public static BigInteger add(BigInteger number1, BigInteger number2) {
 17         return number1.add(number2);
 18     }
 19     
 20     public static BigDecimal add(BigDecimal number1, BigDecimal number2) {
 21         return number1.add(number2);
 22     }
 23     
 24     public static BigDecimal add(BigDecimal number1, BigInteger number2) {
 25         return number1.add(new BigDecimal(number2));
 26     }
 27     
 28     public static BigDecimal add(BigInteger number1, BigDecimal number2) {
 29         return new BigDecimal(number1).add(number2);
 30     }
 31     
 32     /**
 33      * 对减法的封装操作
 34      */
 35     public static BigInteger subtract(BigInteger number1, BigInteger number2) {
 36         return number1.subtract(number2);
 37     }
 38     
 39     public static BigDecimal subtract(BigDecimal number1, BigDecimal number2) {
 40         return number1.subtract(number2);
 41     }
 42     
 43     public static BigDecimal subtract(BigDecimal number1, BigInteger number2) {
 44         return number1.subtract(new BigDecimal(number2));
 45     }
 46     
 47     public static BigDecimal subtract(BigInteger number1, BigDecimal number2) {
 48         return new BigDecimal(number1).subtract(number2);
 49     }
 50     
 51     /**
 52      * 对乘法的封装操作
 53      */
 54     public static BigInteger multiply(BigInteger number1, BigInteger number2) {
 55         return number1.multiply(number2);
 56     }
 57     
 58     public static BigDecimal multiply(BigDecimal number1, BigDecimal number2) {
 59         return number1.multiply(number2);
 60     }
 61     
 62     public static BigDecimal multiply(BigDecimal number1, BigInteger number2) {
 63         return number1.multiply(new BigDecimal(number2));
 64     }
 65     
 66     public static BigDecimal multiply(BigInteger number1, BigDecimal number2) {
 67         return new BigDecimal(number1).multiply(number2);
 68     }
 69     
 70     /**
 71      * 对除法的封装
 72      * 大数浮点数时,结果默认保留10位小数,也可以通过count指定保留小数的位数
 73      * 对于最末一位的取舍采取RoundingMode.HALF_EVEN模式
 74      */
 75     public static BigInteger divide(BigInteger number1, BigInteger number2) {
 76         return number1.divide(number2);
 77     }
 78     
 79     public static BigDecimal divide(BigDecimal number1, BigDecimal number2) {
 80         return number1.divide(number2, 10, RoundingMode.HALF_EVEN);
 81     }
 82     
 83     public static BigDecimal divide(BigDecimal number1, BigDecimal number2, int count) {
 84         return number1.divide(number2, count, RoundingMode.HALF_EVEN);
 85     }
 86     
 87     public static BigDecimal divide(BigDecimal number1, BigInteger number2) {
 88         return number1.divide(new BigDecimal(number2), 10, RoundingMode.HALF_EVEN);
 89     }
 90     
 91     public static BigDecimal divide(BigDecimal number1, BigInteger number2, int count) {
 92         return number1.divide(new BigDecimal(number2), count, RoundingMode.HALF_EVEN);
 93     }
 94     
 95     public static BigDecimal divide(BigInteger number1, BigDecimal number2) {
 96         return new BigDecimal(number1).divide(number2, 10, RoundingMode.HALF_EVEN);
 97     }
 98     
 99     public static BigDecimal divide(BigInteger number1, BigDecimal number2, int count) {
100         return new BigDecimal(number1).divide(number2, count, RoundingMode.HALF_EVEN);
101     }
102     /*
103      * 由于当两个大数都是字符串时,无法通过重载实现,所以才返回Number,以同时适应BigInteger和BigDecimal
104      */
105     public static Number add(String number1, String number2) {
106         if (number1.matches("[0-9]+") && number2.matches("[0-9]+")) {
107             return new BigInteger(number1).add(new BigInteger(number2));
108         } else {
109             return new BigDecimal(number1).add(new BigDecimal(number2));
110         }
111     }
112     
113     public static Number subtract(String number1, String number2) {
114         if (number1.matches("[0-9]+") && number2.matches("[0-9]+")) {
115             return new BigInteger(number1).subtract(new BigInteger(number2));
116         } else {
117             return new BigDecimal(number1).subtract(new BigDecimal(number2));
118         }
119     }
120     
121     public static Number multiply(String number1, String number2) {
122         if (number1.matches("[0-9]+") && number2.matches("[0-9]+")) {
123             return new BigInteger(number1).multiply(new BigInteger(number2));
124         } else {
125             return new BigDecimal(number1).multiply(new BigDecimal(number2));
126         }
127     }
128     
129     public static Number divide(String number1, String number2) {
130         if (number1.matches("[0-9]+") && number2.matches("[0-9]+")) {
131             return new BigInteger(number1).divide(new BigInteger(number2));
132         } else {
133             return new BigDecimal(number1).divide(new BigDecimal(number2), 10, RoundingMode.HALF_EVEN);
134         }
135     }
136     
137     public static BigDecimal divide(String number1, String number2, int count) {
138         return new BigDecimal(number1).divide(new BigDecimal(number2), count, RoundingMode.HALF_EVEN);
139     }
140 }
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测试代码如下:

复制代码
 1 package blog;
 2 
 3 import java.math.BigDecimal;
 4 import java.math.BigInteger;
 5 
 6 public class Main {
 7     public static void main(String[] args) {
 8         String str1 = "46556545";
 9         String str2 = "45454545.45454544";
10         
11         BigInteger num1 = new BigInteger(str1);
12         BigDecimal num2 = new BigDecimal(str2);
13         System.out.println("当两个参数是大数时的测试:");
14         System.out.println("大数加法的测试:");
15         System.out.println(num1 + " + " + num1 + " = " + BigNumberOperation.add(num1, num1));
16         System.out.println(num1 + " + " + num2 + " = " + BigNumberOperation.add(num1, num2));
17         System.out.println(num2 + " + " + num1 + " = " + BigNumberOperation.add(num2, num1));
18         System.out.println(num2 + " + " + num2 + " = " + BigNumberOperation.add(num2, num2));        
19         System.out.println();
20         
21         System.out.println("大数减法的测试:");
22         System.out.println(num1 + " - " + num1 + " = " + BigNumberOperation.subtract(num1, num1));
23         System.out.println(num1 + " - " + num2 + " = " + BigNumberOperation.subtract(num1, num2));
24         System.out.println(num2 + " - " + num1 + " = " + BigNumberOperation.subtract(num2, num1));
25         System.out.println(num2 + " - " + num2 + " = " + BigNumberOperation.subtract(num2, num2));
26         System.out.println();
27         
28         System.out.println("大数乘法的测试:");
29         System.out.println(num1 + " * " + num1 + " = " + BigNumberOperation.multiply(num1, num1));
30         System.out.println(num1 + " * " + num2 + " = " + BigNumberOperation.multiply(num1, num2));
31         System.out.println(num2 + " * " + num1 + " = " + BigNumberOperation.multiply(num2, num1));
32         System.out.println(num2 + " * " + num2 + " = " + BigNumberOperation.multiply(num2, num2));
33         System.out.println();
34         
35         System.out.println("大数除法的测试:");
36         System.out.println(num1 + " / " + num1 + " = " + BigNumberOperation.divide(num1, num1));
37         System.out.println(num1 + " / " + num2 + " = " + BigNumberOperation.divide(num1, num2));
38         System.out.println(num2 + " / " + num1 + " = " + BigNumberOperation.divide(num2, num1));
39         System.out.println(num2 + " / " + num2 + " = " + BigNumberOperation.divide(num2, num2));
40         System.out.println("大数除法保留五位小数:");
41         System.out.println(num1 + " / " + num2 + " = " + BigNumberOperation.divide(num1, num2, 5));
42         System.out.println(num2 + " / " + num1 + " = " + BigNumberOperation.divide(num2, num1, 5));
43         System.out.println(num2 + " / " + num2 + " = " + BigNumberOperation.divide(num2, num2, 5));
44         System.out.println("");
45         
46         System.out.println("###############################################");
47         System.out.println("当两个参数为字符串是的测试:");
48         System.out.println("加法测试:");
49         System.out.println(str1 + " + " + str1 + " = " + BigNumberOperation.add(str1, str1));
50         System.out.println(str1 + " + " + str2 + " = " + BigNumberOperation.add(str1, str2));
51         System.out.println(str2 + " + " + str1 + " = " + BigNumberOperation.add(str2, str1));
52         System.out.println(str2 + " + " + str2 + " = " + BigNumberOperation.add(str2, str2));
53         System.out.println();
54         System.out.println("减法测试:");
55         System.out.println(str1 + " - " + str1 + " = " + BigNumberOperation.subtract(str1, str1));
56         System.out.println(str1 + " - " + str2 + " = " + BigNumberOperation.subtract(str1, str2));
57         System.out.println(str2 + " - " + str1 + " = " + BigNumberOperation.subtract(str2, str1));
58         System.out.println(str2 + " - " + str2 + " = " + BigNumberOperation.subtract(str2, str2));
59         System.out.println();
60         System.out.println("乘法测试:");
61         System.out.println(str1 + " * " + str1 + " = " + BigNumberOperation.multiply(str1, str1));
62         System.out.println(str1 + " * " + str2 + " = " + BigNumberOperation.multiply(str1, str2));
63         System.out.println(str2 + " * " + str1 + " = " + BigNumberOperation.multiply(str2, str1));
64         System.out.println(str2 + " * " + str2 + " = " + BigNumberOperation.multiply(str2, str2));
65         System.out.println();
66         System.out.println("除法测试:");
67         System.out.println(str1 + " / " + str1 + " = " + BigNumberOperation.divide(str1, str1));
68         System.out.println(str1 + " / " + str2 + " = " + BigNumberOperation.divide(str1, str2));
69         System.out.println(str2 + " / " + str1 + " = " + BigNumberOperation.divide(str2, str1));
70         System.out.println(str2 + " / " + str2 + " = " + BigNumberOperation.divide(str2, str2));
71         System.out.println();
72         System.out.println("除法测试:");
73         System.out.println(str1 + " / " + str1 + " = " + BigNumberOperation.divide(str1, str1, 5));
74         System.out.println(str1 + " / " + str2 + " = " + BigNumberOperation.divide(str1, str2, 5));
75         System.out.println(str2 + " / " + str1 + " = " + BigNumberOperation.divide(str2, str1, 5));
76         System.out.println(str2 + " / " + str2 + " = " + BigNumberOperation.divide(str2, str2, 5));
77     }
78 }
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测试结果如下:

当两个参数是大数时的测试:
大数加法的测试:
46556545 + 46556545 = 93113090
46556545 + 45454545.45454544 = 92011090.45454544
45454545.45454544 + 46556545 = 92011090.45454544
45454545.45454544 + 45454545.45454544 = 90909090.90909088

大数减法的测试:
46556545 - 46556545 = 0
46556545 - 45454545.45454544 = 1101999.54545456
45454545.45454544 - 46556545 = -1101999.54545456
45454545.45454544 - 45454545.45454544 = 0E-8

大数乘法的测试:
46556545 * 46556545 = 2167511882337025
46556545 * 45454545.45454544 = 2116206590909090.23190480
45454545.45454544 * 46556545 = 2116206590909090.23190480
45454545.45454544 * 45454545.45454544 = 2066115702479337.5206611570247936

大数除法的测试:
46556545 / 46556545 = 1
46556545 / 45454545.45454544 = 1.0242439900
45454545.45454544 / 46556545 = 0.9763298684
45454545.45454544 / 45454545.45454544 = 1.0000000000
大数除法保留五位小数:
46556545 / 45454545.45454544 = 1.02424
45454545.45454544 / 46556545 = 0.97633
45454545.45454544 / 45454545.45454544 = 1.00000

###############################################
当两个参数为字符串是的测试:
加法测试:
46556545 + 46556545 = 93113090
46556545 + 45454545.45454544 = 92011090.45454544
45454545.45454544 + 46556545 = 92011090.45454544
45454545.45454544 + 45454545.45454544 = 90909090.90909088

减法测试:
46556545 - 46556545 = 0
46556545 - 45454545.45454544 = 1101999.54545456
45454545.45454544 - 46556545 = -1101999.54545456
45454545.45454544 - 45454545.45454544 = 0E-8

乘法测试:
46556545 * 46556545 = 2167511882337025
46556545 * 45454545.45454544 = 2116206590909090.23190480
45454545.45454544 * 46556545 = 2116206590909090.23190480
45454545.45454544 * 45454545.45454544 = 2066115702479337.5206611570247936

除法测试:
46556545 / 46556545 = 1
46556545 / 45454545.45454544 = 1.0242439900
45454545.45454544 / 46556545 = 0.9763298684
45454545.45454544 / 45454545.45454544 = 1.0000000000

除法测试:
46556545 / 46556545 = 1.00000
46556545 / 45454545.45454544 = 1.02424
45454545.45454544 / 46556545 = 0.97633
45454545.45454544 / 45454545.45454544 = 1.00000

posted on 2014-07-18 08:54  锟斤拷锟斤拷  阅读(491)  评论(0编辑  收藏  举报

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