Num62.java
3.4 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
package com.server.utils;
/**
* 62进制数字
*/
public class Num62 {
/**
* 62个字母和数字，含大小写
*/
public static final char[] N62_CHARS = {'0', '1', '2', '3', '4', '5', '6',
'7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w',
'x', 'y', 'z'};
/**
* 36个小写字母和数字
*/
public static final char[] N36_CHARS = {'0', '1', '2', '3', '4', '5', '6',
'7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w',
'x', 'y', 'z'};
/**
* 长整型用N36表示的最大长度
*/
public static final int LONG_N36_LEN = 13;
/**
* 长整型用N62表示的最大长度
*/
public static final int LONG_N62_LEN = 11;
/**
* 长整型转换成字符串
*/
private static StringBuilder longToNBuf(long l, char[] chars) {
int upgrade = chars.length;
StringBuilder result = new StringBuilder();
int last;
while (l > 0) {
last = (int) (l % upgrade);
result.append(chars[last]);
l /= upgrade;
}
return result;
}
/**
* 长整数转换成N62
*/
public static String longToN62(long l) {
return longToNBuf(l, N62_CHARS).reverse().toString();
}
/**
* 长整型转换成N36
*/
public static String longToN36(long l) {
return longToNBuf(l, N36_CHARS).reverse().toString();
}
/**
* 长整数转换成N62
*
* @param length 如不足length长度，则补足0。
*/
public static String longToN62(long l, int length) {
StringBuilder sb = longToNBuf(l, N62_CHARS);
for (int i = sb.length(); i < length; i++) {
sb.append('0');
}
return sb.reverse().toString();
}
/**
* 长整型转换成N36
*
* @param length 如不足length长度，则补足0。
*/
public static String longToN36(long l, int length) {
StringBuilder sb = longToNBuf(l, N36_CHARS);
for (int i = sb.length(); i < length; i++) {
sb.append('0');
}
return sb.reverse().toString();
}
/**
* N62转换成整数
*/
public static long n62ToLong(String n62) {
return nToLong(n62, N62_CHARS);
}
/**
* N36转换成整数
*/
public static long n36ToLong(String n36) {
return nToLong(n36, N36_CHARS);
}
private static long nToLong(String s, char[] chars) {
char[] nc = s.toCharArray();
long result = 0;
long pow = 1;
for (int i = nc.length - 1; i >= 0; i--, pow *= chars.length) {
int n = findNIndex(nc[i], chars);
result += n * pow;
}
return result;
}
private static int findNIndex(char c, char[] chars) {
for (int i = 0; i < chars.length; i++) {
if (c == chars[i]) {
return i;
}
}
throw new RuntimeException("N62(N36)非法字符：" + c);
}
public static void main(String[] args) {
System.out.println(longToN62(Long.MAX_VALUE));
}
}