Conversion between "Go" javabyte[] array and hexadecimal string util------include case and code

Original URL: http://blog.csdn.net/caijunjun1006/article/details/11740223

In Java, Byte uses a binary representation of 8 bits, and we know that each character of the 16 binary needs to be represented by a 4-bit bits (23 + 22 + 21 + 20 = 15), so we can convert each byte to two corresponding 16 characters, That is, the high 4-bit and low 4 bits of byte are converted to the corresponding 16-character H and L, and combined to get the result of byte conversion to the 16 binary string, new string (H) + new String (L). That is, byte represents only 2 bits in hexadecimal notation.

In the same way, the opposite conversion also converts two 16 characters into a byte, as in the same principle.

Based on the above, we can convert the byte[] array to a 16 binary string, and of course we can convert the 16 binary string to the byte[] array.

Here is the tool class that implements conversion between byte[] arrays and hexadecimal strings:

[Java]View Plaincopy

2. Package text.com;
6. Public class Bytesutil {
8. /** 
10. * Convert byte[] to hex string. Convert a byte array to a string
12. * Here we can convert byte to int, then use integer.tohexstring (int) to convert to 16 binary string.
14. * @param src byte[] Data
16. * @return Hex string
18. */
20. public static String bytestohexstring (byte[] src) {
22. StringBuilder StringBuilder = new StringBuilder ("");
24. if (src = = Null | | src.length <= 0) {
26. return null;
28. }
30. For (int i = 0; i < src.length; i++) {
32. int v = src[i] & 0xFF;
34. String HV = integer.tohexstring (v);
36. if (Hv.length () < 2) {
38. Stringbuilder.append (0);
40. }
42. Stringbuilder.append (hv+"");
44. }
46. return stringbuilder.tostring ();
48. }
50. /** 
52. * Convert hex string to byte[] converts a string to a byte array
54. * @param hexstring the hex string
56. * @return byte[]
58. */
60. public static byte[] Hexstringtobytes (String hexstring) {
62. if (hexstring = = Null | | hexstring.equals ("")) {
64. return null;
66. }
68. hexstring = Hexstring.touppercase ();
70. int length = Hexstring.length ()/ 2;
72. char[] Hexchars = Hexstring.tochararray ();
74. byte[] D = new byte[length];
76. For (int i = 0; i < length; i++) {
78. int pos = i * 2;
80. D[i] = (byte) (Chartobyte (Hexchars[pos]) << 4 | chartobyte (Hexchars[pos + 1]));
82. }
84. return D;
86. }
88. /** 
90. * Convert Char to Byte
92. * @param c Char
94. * @return Byte
96. */
98. private static byte chartobyte (char c) {
100. return (byte) "0123456789ABCDEF". IndexOf (c);
102. }
104. }

Here is the test program:

[Java]View Plaincopy

2. Package text.com;
6. Public class Test {
8. public static void Main (string[] args) {
10. byte B1 = 11;
12. byte b2 = 21;
14. byte B3 = 31;
16. byte b4 = 41;
18. byte B5 = 51;
20. byte B6 = 61;
22. byte B7 = 71;
24. byte B8 = 81;
26. byte[] bytes = new byte[] {b1, b2, B3, B4, B5, B6, B7, B8};
28. String hexstring = "0b 1f 3d 47 51";
30. String str = bytesutil.bytestohexstring (bytes);
32. SYSTEM.OUT.PRINTLN ("str--->" + str);
34. byte[] hexstringtobytes = bytesutil.hexstringtobytes (hexstring);
36. For (int i = 0; i < hexstringtobytes.length; i++) {
38. System.out.println ("hexstringtobytes---->" + hexstringtobytes[i]);
40. }
42. }
46. }

Console output:

STR--->0b 1f 3d 47 51
Hexstringtobytes---->11
Hexstringtobytes---->21
Hexstringtobytes---->31
Hexstringtobytes---->41
Hexstringtobytes---->51
Hexstringtobytes---->61
Hexstringtobytes---->71
Hexstringtobytes---->81

ok!

Conversion between "Go" javabyte[] array and hexadecimal string util------include case and code