Base64类源码

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Base64.java 源码:

import java.io.*;   public class Base64 {     private static char[] base64EncodeChars = new char[] {         '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', '0', '1', '2', '3',         '4', '5', '6', '7', '8', '9', '+', '/' };       private static byte[] base64DecodeChars = new byte[] {     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,     52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,     -1,  0,  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, -1, -1, -1, -1, -1,     -1, 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, -1, -1, -1, -1, -1 };       public static String encode(byte[] data) {         StringBuffer sb = new StringBuffer();         int len = data.length;         int i = 0;         int b1, b2, b3;         while (i < len) {             b1 = data[i++] & 0xff;             if (i == len)             {                 sb.append(base64EncodeChars[b1 >>> 2]);                 sb.append(base64EncodeChars[(b1 & 0x3) << 4]);                 sb.append("==");                 break;             }             b2 = data[i++] & 0xff;             if (i == len)             {                 sb.append(base64EncodeChars[b1 >>> 2]);                 sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);                 sb.append(base64EncodeChars[(b2 & 0x0f) << 2]);                 sb.append("=");                 break;             }             b3 = data[i++] & 0xff;             sb.append(base64EncodeChars[b1 >>> 2]);             sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);             sb.append(base64EncodeChars[((b2 & 0x0f) << 2) | ((b3 & 0xc0) >>> 6)]);             sb.append(base64EncodeChars[b3 & 0x3f]);         }         return sb.toString();     }       public static byte[] decode(String str) throws UnsupportedEncodingException {         StringBuffer sb = new StringBuffer();         byte[] data = str.getBytes("US-ASCII");         int len = data.length;         int i = 0;         int b1, b2, b3, b4;         while (i < len) {             /* b1 */             do {                 b1 = base64DecodeChars[data[i++]];             } while (i < len && b1 == -1);             if (b1 == -1) break;             /* b2 */             do {                 b2 = base64DecodeChars[data[i++]];             } while (i < len && b2 == -1);             if (b2 == -1) break;             sb.append((char)((b1 << 2) | ((b2 & 0x30) >>> 4)));             /* b3 */             do {                 b3 = data[i++];                 if (b3 == 61) return sb.toString().getBytes("ISO-8859-1");                 b3 = base64DecodeChars[b3];             } while (i < len && b3 == -1);             if (b3 == -1) break;             sb.append((char)(((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2)));             /* b4 */             do {                 b4 = data[i++];                 if (b4 == 61) return sb.toString().getBytes("ISO-8859-1");                 b4 = base64DecodeChars[b4];             } while (i < len && b4 == -1);             if (b4 == -1) break;             sb.append((char)(((b3 & 0x03) << 6) | b4));         }         return sb.toString().getBytes("ISO-8859-1");     } }

TestBase64.java

public class TestBase64 {public static void main(String[] args) {String s = Base64.encode("wepull1107".getBytes());   //将wepull1107转化为Base64编码System.out.println(s);}}

Base64类 源码

Base64类源码